Troubleshooting

Another streaming host (Sunshine, Apollo, …) is installed

Punktfunk's Moonlight-compatible mode and Sunshine / its forks (Apollo, Vibeshine, Vibepollo, LuminalShine, …) bind the same GameStream ports, advertise the same _nvstream mDNS name, and on Windows often install a conflicting virtual-display driver — and even native-only, Punktfunk's management API and their web UI both want TCP 47990. The symptoms: address already in use in the host log, pairing that silently fails, the wrong host answering a client, display glitches, or a host that "worked until one day it didn't" (a boot race for 47990: Punktfunk exits when it loses, Sunshine just loses its config page).

• Check: punktfunk-host detect-conflicts lists every Sunshine-family host it finds and exits 1 only if one is running or set to start on its own — a dormant leftover (files on disk, a disabled service) prints but exits 0. The host logs the same finding at startup (so it's on the console's Logs page) and carries it in the status summary; the Windows installer warns before installing on the same rule. ss -lptn 'sport = :47990' (Linux) / netstat -ano | findstr :47990 (Windows) shows who holds the port right now.
• Fix: stop and uninstall the other host (sudo systemctl disable --now sunshine; on Windows sc stop SunshineService, then its uninstaller and its display driver), then start Punktfunk.
• Keeping both for a while? Leave GameStream compat off and move Punktfunk's management port (PUNKTFUNK_MGMT_BIND), and on Windows pick a non-exclusive display topology — the whole recipe, and what maps to what when you migrate, is on Switching from Sunshine.

The host isn't found on the network

• Make sure the host is actually running — on Linux systemctl --user status punktfunk-host (or you see it listening in the terminal); on Windows punktfunk-host service status, and if it isn't running see Windows: the host or the web console won't start.

• On an Android phone or TV, check the app's local-network permission. On Android 17 and newer, Android blocks Punktfunk from touching anything on your LAN — discovery, the connect itself, Wake-on-LAN, the game library — until you allow it. The app asks when you open the host list, and a denial looks exactly like a host that isn't there. Tap Allow… under Local network access is off at the top of the host list, or enable Nearby devices for Punktfunk in Android's app settings.

• Host and client must be on the same network/subnet. Discovery uses mDNS, which doesn't cross routed subnets or most VPNs-without-multicast. As a fallback, add the host by IP address in your client.

• A firewall on the host can block it. The native protocol needs two fixed UDP ports open: 9777 (the QUIC control plane) and 5353 (mDNS — this is the one discovery itself runs on). On Linux the packages ship a ready-made punktfunk-native rule that opens both, plus TCP 47990 for the library API:

  sudo ufw allow punktfunk-native                              # ufw (CachyOS, Ubuntu)
  sudo firewall-cmd --permanent --add-service=punktfunk-native \
    && sudo firewall-cmd --reload                              # firewalld (Fedora, some Arch spins)

  The per-session data plane rides a separate, random UDP port and usually needs no firewall rule (see Video is slow to start, or fails across subnets for why, and the one case where opening it helps). GameStream/Moonlight (only with --gamestream) uses TCP 47984/47989/48010 + UDP 47998/47999/48000 (video/FEC 47998, ENet control 47999, audio 48000) + mDNS UDP 5353 — that's the packages' punktfunk-gamestream rule.

• On a Windows host, check the network profile. The installer opens the streaming and console ports on Private and Domain networks only. If Windows has classified your LAN as Public, no client can reach the host — the host logs a warning at startup when it sees this. Set the network to Private in Windows Settings → Network & internet → your network → Network profile type. For a trusted network Windows insists on marking Public, the installer's Allow connections on Public networks option (unattended: /MERGETASKS="allowpublicfw") opts in — but it only takes effect on a first install, so on a PC that already has the host, re-scope the streaming ports from an elevated prompt instead:

  punktfunk-host service install --allow-public-network=on

  That leaves your GameStream choice and the rest of host.env alone. It covers the streaming ports; the web console's own rule for TCP 47992 keeps the scope it was installed with. See Running as a Service → Windows.

The Linux host service won't start

systemctl --user status punktfunk-host shows it failed instead of running. Two common causes:

• There's no host.env yet. The packaged unit reads ~/.config/punktfunk/host.env and won't start until that file exists — no package creates it, they only ship a template to copy:

  mkdir -p ~/.config/punktfunk
  # /usr/share/punktfunk/ on Fedora/Arch/Bazzite, /usr/share/punktfunk-host/ on Ubuntu
  cp /usr/share/punktfunk/host.env.example ~/.config/punktfunk/host.env
  systemctl --user restart punktfunk-host

  On Bazzite copy host.env.bazzite instead of host.env.example.

• status=203/EXEC instead means the unit that ran points at a binary that isn't there — usually an old hand-copied unit in ~/.config/systemd/user/ shadowing the packaged one and still aimed at a source checkout. Remove it, run systemctl --user daemon-reload, and start the packaged unit — see Running as a Service.

The host is asleep and won't wake

Clients wake a saved host by themselves — auto-wake is on by default — but only once they have seen it awake, which is how they learn its MAC address, and only if the machine is armed to answer a magic packet. The arming is what's usually missing, and a Linux host tells you outright: search the web console's Logs page for Wake-on- — Wake-on-LAN for a wired card, Wake-on-WLAN for a Wi-Fi one — and the line either confirms the card is armed or names the interface and the exact command to arm it. A Wi-Fi card is armed by a different command than a wired one, and the log line gives the right one. Windows and macOS hosts don't run that check, so go straight to the BIOS/UEFI and network-card steps in Arming the machine.

Video is slow to start, or fails across subnets

The native data plane (the raw UDP that carries video, separate from the 9777 control plane) uses a random, per-session UDP port — the host binds 0.0.0.0:0, then tells the client which port it got during the connect handshake. There is no fixed data port.

Video flows host → client, but the client sends the first packet: a small hole-punch datagram to that port. This is deliberate. It lets the host learn the client's real (possibly NAT-translated) source address and stream back to it, so a session can cross a NAT or a stateful inter-VLAN firewall without a forwarded data port. What it means for a host firewall:

• Same LAN, no host firewall (or the port allowed): the punch arrives immediately and video starts at once. Nothing to configure.
• Same LAN, host firewall that denies inbound (ufw/nftables/firewalld default): the punch is dropped, so the host waits ~2.5 s, then falls back to the address the client reported and streams anyway — a stateful firewall admits the return traffic because the host sent first. Net effect: it works, but each session takes ~2.5 s longer to start. That slow start is the symptom of a data-plane rule you're missing.
• Across subnets / NAT: the same punch-then-fallback applies, as long as the host's outbound video can reach the client (the path's stateful firewall then admits the return). If the host itself is behind NAT reached only via a forwarded control port, the data path may not establish — this is the case a fixed, forwardable data port would solve.

To remove the ~2.5 s fallback delay, pin the data port in host.env and open exactly that one port. The punch then lands on a port your firewall lets through, so the host answers it at once — no timeout to pay:

# ~/.config/punktfunk/host.env (Linux) · %ProgramData%\punktfunk\host.env (Windows)
PUNKTFUNK_DATA_PORT=9779

systemctl --user restart punktfunk-host    # pick the change up (Windows: punktfunk-host service restart)
sudo ufw allow 9779/udp                    # open exactly that one port

Running serve by hand instead? Pass --data-port 9779 on that command line — but don't start one alongside the service, which already holds these ports.

One caveat. A fixed data port serves one session at a time; a second concurrent session finds it busy and transparently falls back to a random port (logged). Pinning changes nothing about how video is addressed — the host still waits for the client's punch and answers whatever source it heard from, which is what lets a forwarded port or a port proxy work behind the client's own NAT. On a normal single-LAN setup you can also just leave the data port closed and accept the one-time ~2.5 s punch-timeout, or not run a host firewall on a trusted LAN at all.

nvidia-smi says it can't communicate with the driver

The NVIDIA kernel module didn't load. With Secure Boot enabled (mokutil --sb-state), the module is signed with a locally generated key that must be enrolled once — or disable Secure Boot in firmware, fine for a dedicated box. Import the key, reboot, and on the blue MOK Manager screen (on the machine's own console, not over SSH) choose Enroll MOK → Continue → Yes → (the password) → Reboot:

sudo mokutil --import /var/lib/shim-signed/mok/MOK.der     # Ubuntu
sudo mokutil --import /var/lib/dkms/mok.pub                # Debian (DKMS-built module)
sudo akmods --force && sudo mokutil --import /etc/pki/akmods/certs/public_key.der   # Fedora (akmod)

After a kernel update the module may need a rebuild — reinstall the driver package. Then confirm nvidia-smi loads and cat /sys/module/nvidia_drm/parameters/modeset prints Y (Wayland needs KMS; if it doesn't, echo 'options nvidia-drm modeset=1' | sudo tee /etc/modprobe.d/nvidia-drm.conf, regenerate the initramfs, reboot).

systemctl --user status punktfunk-web: unit not found

The web console is its own package, and the punktfunk RPM only recommends it (Recommends: punktfunk-web) — a box with install_weak_deps=False in /etc/dnf/dnf.conf, a --setopt=install_weak_deps=0 install, or an rpm-ostree layering that drops weak deps gets the host with no console and no unit to enable. Install it by name:

rpm -q punktfunk-web || sudo dnf install punktfunk-web punktfunk-scripting
systemctl --user enable --now punktfunk-web
journalctl --user -u punktfunk-web-init | sed -n 's/.*password generated: //p'

No match for argument instead means the repo you're on has no console: COPR builds host and client only (its mock chroot has no bun). Use the RPM registry — Fedora, step 2. The same weak-dep miss happens on Debian/Ubuntu after an apt install --no-install-recommends; the fix is sudo apt install punktfunk-web.

pacman: error: could not register 'punktfunk' database (database already registered)

The repo block got appended to /etc/pacman.conf twice — the add line is an append, so running it a second time leaves two [punktfunk] sections, and every later pacman run opens with this line. It's harmless (pacman ignores the duplicate), but to silence it delete the extra block from /etc/pacman.conf. (The current add line checks first and won't append a second copy.)

The desktop won't start, or "GPU … not supported by EGL"

The NVIDIA GL/EGL userspace is missing — the base driver package doesn't always include it.

• Ubuntu: sudo apt install libnvidia-gl-<version> (matching your driver).
• Confirm /usr/share/glvnd/egl_vendor.d/10_nvidia.json exists and nvidia-drm modeset is Y.

See GNOME for the GL/EGL userspace details.

Black screen / no picture, but the client connects

• You must be on a Wayland session, not X11 (check the login-screen session picker).
• KWin must be ≥ 6.5.6 (kwin_wayland --version) for the headless appliance session (kwin_wayland --virtual); a normal Plasma 6 login needs no particular version, only the screencast grant. GNOME ≥ 48; gamescope ≥ 3.16.22. See KDE for the KWin/Wayland requirement and gamescope for the gamescope one.
• If host.env sets PUNKTFUNK_COMPOSITOR, remove it — the host auto-detects the live compositor, and the pin points it at one backend even when a different session is live (it also disables Gaming ↔ Desktop following).

A library launch says "Unable to open a connection to X" (Linux)

Steam — or Lutris, or a native X11 game — opens that dialog instead of the game, and the same title launches fine once you have started Steam yourself. The host had no DISPLAY to hand the child: a systemd --user host starts before the session exports one, and systemctl --user import-environment never reaches a unit that is already running. The second attempt works because a Steam client that is already up takes the steam:// URL over its own pipe and never needs X.

Hosts after 0.35.0 read the session's display at each launch, so update first. On an older one, add DISPLAY=:0 to ~/.config/punktfunk/host.env (ls /tmp/.X11-unix/ names the number) and systemctl --user restart punktfunk-host.

Games from my library open on a physical monitor, not on the stream (Hyprland / sway)

The stream shows your bare desktop while the game is running on a screen at the machine. On Hyprland and sway the virtual display is an extend output — it's added beside your real monitors, and neither compositor moves anything onto a new output by itself. Both open a new window on whatever monitor holds focus, so a session that never claims focus launches everything onto the monitor you were last using in person.

The host now claims focus for the streamed display at session start and again just before each library launch, which is the fix — if you're seeing this, update first, since hosts up to and including 0.29.0 never claimed it at all. The host log says which head it took (focused the streamed headless output), and warns when it couldn't.

If it still happens on a host that has the fix:

• Are you also using the machine in person? Focus is per-monitor and live: clicking on a physical monitor while the game is still starting pulls the new window over to it. Launch, then leave the host's own keyboard and mouse alone until the game is up.
• A launcher that opens a second window later (Steam Big Picture, Heroic, some emulator front-ends) places that window wherever focus is at that moment, not where the first one went. If this is your normal way to play, set Virtual displays → Dedicated game sessions to Dedicated — every launch then gets its own headless gamescope with only the game inside, and placement stops being a question of focus at all (needs gamescope installed).
• Setting the topology to Primary won't do it. Wayland has no primary output for these two backends to set, so Primary behaves as Extend and the host says so in the log. Exclusive is implemented here — it switches your physical monitors off for the session and back on afterwards, which does put every window on the stream. See Virtual displays → Topology.

The screen stays black after switching to Game Mode (Nobara)

On distros whose Game Mode is display-manager autologin under plasmalogin (Nobara), a managed takeover from a host 0.19.1 or older could kill the display manager: it trips systemd's start limit and the box stays black until someone restarts it. Recover from a VT (Ctrl+Alt+F3) or SSH:

systemctl --user unmask --runtime 'gamescope-session-plus@*.service'
sudo systemctl reset-failed plasmalogin && sudo systemctl restart plasmalogin

Current hosts detect the display-manager flavor and never mask the session unit there — see gamescope → autologin display managers for the polkit rule that enables the full managed takeover on these boxes (without it the host mirrors Game Mode instead).

Game Mode: black screen on connect, or the stream is stuck at the box's resolution

You connect to a box that autologins into Steam Gaming Mode and get a black picture every time — or a picture at the box's own resolution instead of the one your client asked for, with the box's monitor still lit. Nothing errors: the client connects, the host logs no failure, no unit is failed.

The managed takeover is being refused and the host is falling back to mirroring the box's own session. On a box whose panel is off (a headless appliance, a TV that's been switched away) there is nothing to mirror, so the fallback is a black screen. Almost always the cause is group membership: the takeover stops the display manager through a root helper, and that helper serves members of the punktfunk group only.

id -nG | tr ' ' '\n' | grep -x punktfunk      # are you in it?
journalctl --user -u punktfunk-host | grep -iE "punktfunk. group|takeover unavailable"

The host also checks at startup on any box that will need the takeover, so a fresh systemctl --user restart punktfunk-host puts the answer at the top of the log. The fix is one command and a fresh login:

sudo usermod -aG punktfunk "$USER"   # then log out and back in

Read the reason the log quotes before doing anything else. The takeover has three other ways to be refused — no packaged helper (a tarball or source install), no polkit on the box, and polkit denying the action — and the host now prints which one it hit, verbatim from the privileged path. Hosts up to 0.27.0 printed a fixed guess instead ("reinstall the punktfunk package, or install the display-manager polkit rule from the docs"), and on the group case both of those suggestions were dead ends: neither adds anyone to a group.

Two things this is not: it isn't the pad group problem (same group, different symptom), and it isn't lingering — though a host with no login session of its own enables lingering through the same helper, so an unjoined user often sees "enabling lingering failed" first. Both are covered in gamescope → autologin display managers.

Session fails right after editing host.env

• Keys are case-sensitive: punktfunk_gamescope_attach=1 sets nothing — use the exact uppercase names.
• Hardcoded session anchors with the wrong uid (XDG_RUNTIME_DIR=/run/user/1000 when id -u isn't 1000) point the host at another user's PipeWire/D-Bus: audio errors like pw audio connect … Creation failed, no capture, and clients reporting the host as unreachable or asleep. Delete both anchor lines — a systemctl --user service doesn't need them — or fix the uid.
• PUNKTFUNK_COMPOSITOR pins the backend and disables Gaming ↔ Desktop following — remove it on any box that switches sessions.
• The env file is read at service start: systemctl --user restart punktfunk-host after edits.

Capture fails: "Session creation inhibited" (GNOME)

A locked GNOME session blocks screen capture. On an always-on/headless host, disable the lock:

gsettings set org.gnome.desktop.screensaver lock-enabled false
gsettings set org.gnome.desktop.session idle-delay 0

See GNOME → Headless session and Running as a Service.

My mouse and keyboard are stuck in the stream

Nothing is broken — the stream captures them on purpose, from the moment it starts and again whenever you click into it, so your keys and pointer go to the host instead of your own desktop. Ctrl+Alt+Shift+Q hands them back (⌃⌥⇧Q on macOS), and with a pad in your hands L1+R1+Start+Select does the same on the Linux, Windows and Steam Deck clients. Whatever you were holding down is released on the host, so nothing sticks. The rest of the in-stream chords — switch mouse mode, disconnect, fullscreen — are in Getting your input back.

My keyboard types the wrong characters (# comes out as \)

A German keyboard giving \ for #, ' for ä and / for -, or z and y swapped, is a host layout mismatch — the client is fine.

Punktfunk sends the physical key you pressed, not the character, exactly as a keyboard plugged into the host would. What that key finally types is decided by the layout the host session is running, so the host has to be set to the same layout as the keyboard you're typing on. When it isn't, every key whose position differs between the two layouts comes out as its neighbour.

On Linux, set the layout the normal way and reconnect:

sudo localectl set-x11-keymap de pc105 nodeadkeys   # your layout, model, variant

Punktfunk reads that setting and hands it to the session on the next connect. Two things are worth knowing:

• Wayland desktops don't read it by themselves. localectl writes a file only Xorg opens, so before this release a correctly-configured box could still run a US session. If your compositor is already set to the right layout in its own settings, nothing changes.
• Game Mode needs a current punktfunk-gamescope. Gamescope publishes no keyboard layout at all to the apps it runs, so Steam and games saw US whatever the box was set to. Our build fixes that from +pfhdr8 on — check with punktfunk-gamescope --version, and update if it's older.

Nothing here changes which physical key does what in a game: WASD stays under the same fingers on every layout.

A controller is detected but games don't see it

• Linux. The host user needs to be in the input group. On Bazzite:

  ujust add-user-to-input-group

  Then log out and back in. On other distros this is sudo usermod -aG input $USER + re-login. See Bazzite.

• Windows, if this PC ever ran 0.22.0 or 0.22.1. On those two releases the default emulated controller bound one of Windows' own drivers instead of Punktfunk's, so the app responded to your controller normally but no game ever saw it. It's fixed from 0.22.2 on — but you have to update through the installer: the setup .exe, winget upgrade, or the console's Update now button (see Updating). Swapping punktfunk-host.exe by hand does not fix it, because the stale controller device keeps the driver it was already bound to.

The pad works, but arrives as an Xbox 360 controller instead of a Steam Deck

Only the virtual Steam Deck controller (paddles, trackpads, gyro) is missing here — ordinary gamepad input is fine. That pad reaches games as a real USB device over usbip, and the sysfs files it attaches through are owned by a group called punktfunk, separate from input. Four things have to line up on the Linux host, and none of them announces itself when it doesn't:

getent group punktfunk                         # the group exists at all
id -nG | tr ' ' '\n' | grep -x punktfunk       # ...and you are in it
ls -l /sys/devices/platform/vhci_hcd.0/attach  # owned by punktfunk, mode 0660
lsmod | grep vhci_hcd                          # the transport module is loaded

If the group is missing entirely, the udev rule tried to chgrp to a group nobody created, so the nodes stayed root-only. That was the case on installs that reached 0.25.0 by upgrade on Arch, on NixOS, on the Bazzite sysext, and on Steam Deck source installs. Re-running your package manager's upgrade (or update.sh on a Deck) creates it now; otherwise sudo groupadd --system punktfunk by hand. Then sudo usermod -aG punktfunk "$USER" and log out and back in — group changes only reach the host's systemd --user service on a fresh login, and on a Deck a reboot is the reliable way to get one.

Joining the group is optional, and there is a real reason it is not automatic: writing that attach file materialises an arbitrary emulated USB device. Skip it on a machine you share.

It is not only the pad, though: the same group authorizes the helper that stops the display manager for a managed Gaming Mode takeover, so on a box that autologins into Game Mode, skipping it also costs you the takeover.

Stream lags, then freezes, with a DualSense pad (Bazzite, SELinux)

On Bazzite (and other SELinux-enforcing Fedora Atomic spins), a DualSense / DualShock 4-type virtual pad can make the stream lag and then freeze — gamescope at 0 fps, tx_mbps collapsing — measured live on Bazzite 43. The virtual pad binds the kernel's hid-playstation driver, and Valve's ds_inhibit (inside steamos-manager) reacts to any such hidraw by walking /proc/*/fd/ on every open/close. SELinux denies steamos_manager_t that walk — ~324 avc: denied per second — and setroubleshootd amplifies the flood into a box-wide fork storm that starves the stream.

Two traps while diagnosing: the AVC lines read comm="tokio-rt-worker" — that is steamos-manager, not punktfunk (check scontext=…steamos_manager_t…); and once started, the setroubleshootd storm outlives the denials by 15+ minutes, so the box stays starved after the pad is gone.

• Fix: punktfunk ships a dontaudit SELinux drop-in that silences the flood (ds_inhibit then simply leaves the pad uninhibited — harmless). The sysext installs it on install/update; on an existing install run sudo punktfunk-sysext reapply. On a layered or bootc host: sudo semodule -i /usr/share/punktfunk/selinux/punktfunk-ds-inhibit.cil (remove with sudo semodule -r punktfunk-ds-inhibit).
• Hardening, recommended on any streaming host: sudo systemctl mask --now setroubleshootd. It is purely a desktop alert daemon — nothing depends on it (systemctl list-dependencies --reverse setroubleshootd returns only itself) — and masking it makes the box robust against any AVC burst. Reversible with unmask.
• Workaround with a feature loss: set the client's controller type to Xbox 360 (uinput, no hid-playstation) — costs adaptive triggers, lightbar and touchpad. The host-side PUNKTFUNK_GAMEPAD knob does not help: an explicit client choice outranks it.

A Steam Controller 2 is captured, but Steam's controller list stays empty

The client says everything is fine — the Controllers screen shows Steam Controller 2, captured, streams as-is — and on the host Steam's Settings → Controller → Connected Controllers has nothing in it. Buttons do nothing in games, and the trackpads don't move the pointer.

Unlike every other pad Punktfunk presents, the Steam Controller 2 has exactly one consumer: Steam. No kernel driver claims its product id — mainline hid-steam stops at the Deck — and its state reports ride a vendor collection, so the pad produces no evdev node for anything else to read. If Steam can't open its hidraw node, you don't get a degraded controller, you get no controller.

On a Windows host, stop here — the rest of this section is Linux only. Windows has no udev and no permission gate to open: the pad is a UMDF device the pf_gamepad driver package serves, so Steam reaches it as soon as the devnode enumerates. An empty controller list there means the driver package is missing or stale instead. Reinstall it and reconnect:

punktfunk-host.exe driver install --gamepad

The node is root-only until a udev rule says otherwise, and distro steam-devices rule sets are per-product-id: a host whose copy predates the SC2 (it shipped in 2026) never grants it. Punktfunk ships the rule itself from 0.30.0 on. On an older host, add it by hand:

sudo tee /etc/udev/rules.d/61-punktfunk-sc2.rules >/dev/null <<'EOF'
KERNEL=="hidraw*", KERNELS=="*28DE:1302*", GROUP="input", MODE="0660", TAG+="uaccess"
KERNEL=="hidraw*", KERNELS=="*28DE:1304*", GROUP="input", MODE="0660", TAG+="uaccess"
KERNEL=="hidraw*", ATTRS{idVendor}=="28de", ATTRS{idProduct}=="1302", GROUP="input", MODE="0660", TAG+="uaccess"
KERNEL=="hidraw*", ATTRS{idVendor}=="28de", ATTRS{idProduct}=="1304", GROUP="input", MODE="0660", TAG+="uaccess"
EOF
sudo udevadm control --reload-rules && sudo udevadm trigger

Then end the session and reconnect, so the pad re-enumerates under the new rule. 1302 is the wired controller and 1304 the Puck dongle — the two identities the host presents.

To confirm this is what you're hitting, look at the host log for one line and one absence: the pad attaching (attached via usbip), and no answering feature GET afterwards. That pair means the kernel enumerated the controller and Steam never opened it. The everything-else checks — the punktfunk group, vhci_hcd, the attach node — are in the virtual Steam Deck section above; if attached via usbip is missing from the log entirely, start there instead.

One more thing that is not a bug: with Punktfunk capturing, the trackpads stop working as a mouse whenever Steam isn't running. Punktfunk turns the controller's built-in mouse-and-keyboard emulation ("lizard mode") off so it can read the full report stream, so on this pad Steam is what makes the trackpads a pointer — exactly as on a Steam Deck in desktop mode.

Copy and paste between host and client does nothing

The shared clipboard needs two separate switches on, and turning on only one looks exactly like the feature not existing: the host operator has to allow it with PUNKTFUNK_CLIPBOARD in host.env and restart the host, and you have to turn it on for that one host in your client's Edit… sheet. Work through Why the toggle does nothing — it also names the clients and host sessions where nothing crosses no matter what you set.

A plugin's interface doesn't load

The plugin's page in the console opens — title, version, Open in new tab — but the panel below it stays empty.

Plugin interfaces are served on TCP 47993, a separate port from the console's 47992, so that a plugin can't act as you with your logged-in session (see Two ports, not one). An empty panel means the browser can't load anything from that second port. Two reasons, in order of likelihood:

• The port isn't open. Only the console's port is reachable, so the frame has nothing to show. On a host you upgraded, this is the usual answer: an already-open firewall does not pick up a port that a later version added, because the rule it saved lists the ports it knew at the time.

  # ufw (CachyOS, Ubuntu): re-expand the profile, then reload
  sudo ufw app update punktfunk-web && sudo ufw reload
  
  # firewalld (Fedora, Bazzite, Nobara): re-read the shipped service definition
  sudo firewall-cmd --reload

  # Windows: re-run the service installer, which re-adds both console rules
  punktfunk-host service install

  Check what's actually open with sudo ufw status verbose or sudo firewall-cmd --info-service=punktfunk-web — you want 47993 listed next to 47992.

• The certificate isn't trusted for that port yet. Browsers keep a self-signed certificate exception per port, and a warning page can't be shown inside a panel. The console detects this and offers a link to open the plugin in its own tab: accept the warning there once and come back.

If the panel is empty and the console shows no explanation at all, the plugin's own port is probably being dropped rather than refused — open 47993 as above.

Pairing is rejected / the client can't connect

• The host requires pairing by default. Arm pairing from the web console, then enter the PIN on the client. See Pairing & Trust.
• If you re-installed the host, its identity changed — re-pair the client.

The picture freezes for a moment, over and over (Windows)

A freeze that comes back on a rhythm — every few seconds, every minute, always the same gap — is not a bandwidth problem, and lowering the bitrate won't touch it. The Windows capture path detects that pattern itself and writes the cause and the cure into the log.

Start on the Status page: while a session runs, its card shows Capture health — the capturer's own verdict, refreshed twice a second. healthy and idle need no action (an idle desktop composes nothing, and that is fine). suspect means the source stopped while the desktop still shows signs of life; stalled (worker) / (transport) / (conversion) / (presentation) names the leg that lost the frames, and Last recovery shows what the host did about it: the stall class, each rung it ran with its outcome, and whether real frames came back. A failed episode ends the video plane with a typed error and the session rebuilds its capture; repeated failures back off (the cooldown is in the same block of GET /api/v1/status). Only when that line does not explain the rhythm, go to the log:

Open the web console's Logs page and search for METRONOMIC. You'll get one of two lines:

• …and coincide with Windows monitor hot-plug/re-enumeration events — a display (or its cable, switch or AVR) is re-probing its link on a timer and Windows reacts every time. Cures, best first: turn that display's auto input scan/detect off in its own OSD (on TVs also instant-on / quick-start and CEC), unplug its cable at the GPU, fit an HPD-holding adapter or dummy plug, or simply keep the display active while you stream. The console's Virtual displays page also has a Disable monitor devices while streaming (PnP) toggle that suppresses the Windows-side reaction; the log line's connected_inactive field names the displays it suspects.
• …with NO coinciding OS display event — the disturbance is below Windows: a connected but sleeping screen being serviced by the GPU driver, display-poller software (the SteelSeries GG / SignalRGB class), or the desktop present clock — try a different refresh rate. On a laptop panel that the host deactivated, keeping it active with the primary topology usually settles it — see Virtual displays → Topology. As a last resort, lowering the GPU-priority defaults (setx /M PFVD_NO_RT_GPU 1 + a device restart, and PUNKTFUNK_GPU_PRIORITY_CLASS=high; the line's rt_gpu_driver / rt_gpu_host fields show what is engaged) has quieted this pattern on some AMD machines — but it masks the disturbance rather than fixing it, and costs stream latency under load.

Freezes that repeat without a steady rhythm are caught too: search the log for REPEATING without a stable period — that warning carries the same fields and the same cure list. Every session also stamps one GPU-priority posture for this capture session line near its start, so a log shows the levers even before any stall fires.

Stutter, drops, or high latency

• Lower the bitrate. On a busy or Wi-Fi link, the requested bitrate may be too high — the native clients' speed test picks a safe value; with Moonlight, set it manually.
• Prefer a wired connection or 5 GHz Wi-Fi between host and client.
• Streaming to many devices at once shares the GPU encoder. The host serves several concurrent native sessions (up to 4 by default); heavy load is usually bitrate-bound, so lower the bitrate first.

If the stream is wrong rather than late — a codec you didn't pick, 8-bit where you expected HDR, 4:2:0 where you asked for full chroma — the answer is usually that the host declined the request and told your client so. When the client and the host disagree lists what it does with each one.

Audio stutters, and only the audio (Linux)

Video steady, sound broken up: on a Linux host, look for this line in the host log.

WARN  our audio capture group is being clocked by another node — every hole in this stream is
      that node's scheduling, not ours … driver="alsa_input.usb-…" expected="punktfunk-speaker-…"

PipeWire schedules audio in groups, and each group runs on one node's clock. The host brings its own — the virtual output it records — so this warning means something has linked that output to another device and handed it the clock instead. Whatever the named device does with its timing, your stream now does too: if it stalls for 30 ms, so does the audio, and the host fills the hole with silence.

The usual cause is a loopback from the host's virtual output to a real one (some "listen to this device" setups create exactly that). The pathological case is a sound card reached over the network — a controller forwarded with VirtualHere or USB/IP presents one, and its clock cannot be recovered across the link at all; a host in that state synthesized 15 % of everything the user heard. Remove the loopback, or turn off that card's audio profile (KDE → Audio → the device → Profile → Off), and the group goes back to the host's own clock.

Without the warning, audio stutter is the same problem as any other stutter — see above.

Streamed audio sounds worse than the host does

The host does not capture "the sound card" — it captures a render endpoint, and by default it picks one that is silent on the host so the audio plays on your client only. On a PC with Steam installed that silent endpoint is Steam's Streaming Microphone, which exists to carry remote voice. If Windows has it configured as a narrow device — mono, or below 48 kHz — then the whole desktop mix is squeezed through that before it is ever encoded, and no amount of bitrate will bring it back.

Since 0.25 the host checks for this: it reads each candidate endpoint's real format, prefers a real output device over a narrow virtual one, and says so in the log —

WARN  the desktop-audio loopback endpoint mixes at 24000 Hz, so the stream is band-limited …
INFO  audio loopback capturing device="…" engine_hz=48000 engine_ch=2 engine_bits=32

That engine_* line is the endpoint's own format, so it tells you directly whether the source was ever full quality. To choose the routing yourself, set in host.env:

# client_only     — default; audio plays on the client only (a silent endpoint)
# host_and_client — capture a real output device; audio plays on BOTH ends
# follow_default  — capture whatever YOUR default playback device is, and never change it
PUNKTFUNK_AUDIO_OUTPUT_MODE=host_and_client

host_and_client is also the quickest way to A/B the problem: if the stream sounds right that way and wrong on the default, the endpoint was the cause.

Two related knobs:

PUNKTFUNK_AUDIO_QUALITY=high    # low | standard | high (default high — stereo 256 kbps)
PUNKTFUNK_AUDIO_REDUNDANCY=1    # force the loss-resilient audio plane on (default: automatic)

Both are a request, not a guarantee: the host budgets audio against the session's video bitrate and steps it down on a narrow link, because audio is not managed by adaptive bitrate — so whatever it takes is taken off the top. On a roomy link you get 256 kbps plus loss redundancy; as the link narrows the host drops redundancy first, then the tier, and never goes below ~96 kbps. The session log line says what it settled on:

INFO  punktfunk/1 audio streaming … tier=high kbps=512 redundancy=true

standard reproduces the pre-0.25 encoder exactly if you want to A/B it.

If what you want is no lossy stage at all, ask for it in the client: its audio-format setting has a Lossless row per rate, and picking one is the whole opt-in. There is nothing to set on the host — the host allows the lossless plane by default. If you want to forbid it on this host regardless of what clients ask for, that is the same variable, inverted:

PUNKTFUNK_AUDIO_HIRES=0         # refuse the lossless PCM audio plane (default: allowed)

The plane replaces Opus with uncompressed PCM — 44.1 through 176.4 kHz, 16 or 24-bit, stereo through 7.1 — and it costs 1.4–8.5 Mbps in stereo (up to 33.9 for 176.4 kHz/24-bit 7.1) against Opus's 256 kbps. Like every other audio setting here, that comes off the top of the link, where adaptive bitrate can neither see it nor reclaim it. Which is why the client's setting ships off and the host's affordability check is unconditional: a session only goes lossless when it can pay for it out of a quarter of its video bitrate.

It is also unlikely to fix the problem this section is about: a lossless copy of a 24 kHz mono mix is still a 24 kHz mono mix, so fix the endpoint first. What it buys is bit-exactness rather than audibly better sound — on game content, 256 kbps Opus is already effectively transparent. On Windows the host reads the endpoint's own engine rate (the engine_hz line above) and refuses to pad, so 96 kHz means setting that device to 96 kHz in Windows' own sound properties. A Linux host normally owns the sink applications play into and states its rate to the audio graph itself, so 96 kHz there needs no device configuration at all. Whenever any condition fails — the client didn't ask, this host has PUNKTFUNK_AUDIO_HIRES=0, the capture path can't genuinely deliver the rate, the link can't spare it, or one frame of that format won't fit a datagram at that channel count — the session quietly stays on Opus and the log says which one lost. That log line is worth knowing about before you go looking in the UI: a declined session and a granted one look the same from the settings screen, and the host's journal is where the reason lives.

One trap if the box you are editing is also a client: the Linux and Windows clients read a PUNKTFUNK_AUDIO_HIRES of their own, with a richer grammar — a bare rate such as 96000, or an explicit 96000/24 — so one line in a shared environment sets both halves at once. 0 is the value that means off to each of them, which is why the opt-out line above is written that way; anything that isn't 0/false/off/no reads as allow on the host side, so a client-shaped 96000/24 also leaves the host's half permissive. The client's spellings are in Configuration → Client-side.

Audio lags behind the picture

The client buffers a little audio to absorb network jitter. Since 0.25 that buffer corrects itself: if it drifts deeper — a Wi-Fi burst, a stall, or just the two devices' clocks running at fractionally different speeds — it trims itself back a few milliseconds at a time, inaudibly. Before, it could only grow, so a single hiccup left audio permanently behind the video and the only cure was reconnecting.

If audio is still noticeably late:

• Reconnect once. It confirms whether the delay was accumulated (gone after a reconnect) or constant (something else).
• Check for underruns rather than guessing. The client logs its buffer depth periodically; a rising underruns count means the buffer is being starved, which is a network or CPU problem, not a buffering one.
• Wired or 5 GHz Wi-Fi. Arrival jitter is what the buffer exists to absorb; less jitter lets it run shallower.

Windows: the host or the web console won't start

The PunktfunkHost service runs both halves of the Windows host: the streaming host itself and the web console. It restarts either one automatically if it stops, so most console outages heal themselves within a minute. The service commands need an elevated PowerShell or Command Prompt.

1. Is the service running?

   punktfunk-host service status
   punktfunk-host service restart

   restart stops it, waits for it to actually reach Stopped, and starts it again.

2. Two punktfunk-host.exe processes in Task Manager is normal — don't kill one. The service itself runs as SYSTEM in session 0, where it can neither capture the screen nor inject input, so it launches a second copy into the interactive session and supervises it. One supervises, one streams.

3. The console page never loads. The service restarts the console on any failure, so give it a minute first. If it stays down, the console's own log says why — check %ProgramData%\punktfunk\logs\web.log (and service.log next to it, which records every console start and exit). Those files are readable only by Administrators and SYSTEM, so open them from an elevated PowerShell — Get-Content -Tail 50 $env:ProgramData\punktfunk\logs\web.log — then restart the service:

   punktfunk-host service restart

   Right after a very first install the console can lag the host by a few seconds on purpose: it waits for the host to finish writing its certificate before serving.

4. The status icon is missing after an update. Windows only launches the tray at sign-in, and an upgrade closes the running ones. Put it back without signing out — from your normal (not elevated) shell, so it runs as you:

   punktfunk-host tray start

   punktfunk-host tray status says whether one is running and where it is installed. See Windows Host → Status tray.

Windows: "Punktfunk Virtual Display" shows Code 10 in Device Manager

Sessions end with "pf-vdisplay driver interface not found" and Device Manager shows the Punktfunk Virtual Display device failed with Code 10 (STATUS_DEVICE_POWER_FAILURE). (Installs older than 0.22.2 spell that device name in lower case.)

This means your Windows version is too old. The virtual-display driver requires the IddCx 1.10 driver framework, which first shipped in Windows 11 22H2 (build 22621) — on Windows 10 (including LTSC) and Windows 11 21H2 the driver installs but cannot start. Reinstalling won't help; the fix is updating to Windows 11 22H2 or newer. (Current installers refuse to run on older Windows for this reason; if you see this, the host was likely installed with an older installer.)

Still stuck?

Read the host's log around the failed connect or capture.

1. Open the web console's Logs page. It always holds the host's recent output at debug detail, whatever the log level is set to — there's nothing to switch on and no restart needed.
2. Filter it down to the level or the text you're after. The Host / Plugins switch beside the level buttons picks the producer: your plugins log to the same page, tagged plugin:<name>, so a misbehaving plugin is one click away rather than a separate hunt through the journal.
3. Use Download logs to save exactly what you're filtering on as a timestamped .log file you can attach to a bug report. The button beside it hands the same text to your phone or tablet's share sheet, or copies it to the clipboard on a desktop.

The same output also lands outside the console — on Linux in the journal (journalctl --user -u punktfunk-host), on Windows in %ProgramData%\punktfunk\logs\host.log (plus service.log for the service that supervises it). Those do follow the log level: raise it with RUST_LOG=debug in host.env and restart the host. RUST_LOG=info is already the default, so setting it changes nothing. The Windows files are readable only by Administrators and SYSTEM — a normal editor is refused even on an admin account, because Windows hands it a filtered token — so open them from an elevated PowerShell, or stay on the Logs page above, which needs no elevation.

None of that covers the client side. If the picture, the decoder or the presenter is what failed, the Windows client keeps its own log at %LOCALAPPDATA%\punktfunk\logs\client.log (rotated to .old at the next start once it passes 10 MB, one generation kept) — that's the only place a receive, decode or present failure is recorded.

For a performance problem rather than a failure, attach a recording instead of a log: see Recording a capture for a bug report.