punktfunk/docs-site/content/docs/troubleshooting.md

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Troubleshooting	Common problems setting up or using a Punktfunk host, and how to fix them.

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

Punktfunk is a Moonlight-compatible host. So are Sunshine and its forks (Apollo, Vibeshine, Vibepollo, LuminalShine, …). Running one of them at the same time as Punktfunk is not supported: they bind the same GameStream ports (47984/47989 and 47998–48010, plus a web UI on 47990 that collides with Punktfunk's management API), advertise the same _nvstream mDNS name, and often install a conflicting virtual-display driver. The result is address already in use errors, pairing that silently fails, the wrong host answering a client, and capture/display glitches.

• Punktfunk detects this automatically. It warns in the host's startup log — so it's on the web console's Logs page — and carries the finding in the status summary the management API serves. The Windows installer additionally warns before installing, but only when a competing host's service is set to start on its own; a dormant install isn't flagged. The tray icon doesn't flag it at all. To check on demand, run:

  punktfunk-host detect-conflicts
  

  It lists any conflicting host found (installed or running) and exits non-zero if there is one.

• Fix: stop and uninstall the other host, then start Punktfunk — e.g. stop the service (sudo systemctl disable --now sunshine / on Windows sc stop SunshineService) and uninstall it. If you only want to try Punktfunk without removing the other host, at least make sure the other host is fully stopped first (they cannot both run at once).

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-LAN, and the line either confirms the card is armed or names the interface and the exact command to arm it. 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 host then binds that fixed port, skips the punch-wait, and streams straight to the client — no timeout to pay:

# ~/.config/punktfunk/host.env (Linux) · %ProgramData%\punktfunk\host.env (Windows)
PUNKTFUNK_DATA_PORT=9778

systemctl --user restart punktfunk-host    # pick the change up (Windows: punktfunk-host service restart)
sudo ufw allow 9778/udp                    # open exactly that one port

Running serve by hand instead? Pass --data-port 9778 on that command line — but don't start one alongside the service, which already holds these ports.

Two caveats. 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 + hole-punch (logged). And --data-port streams to the client's reported address, so use it only where that address is reachable — a flat LAN, or a port-forward that doesn't remap the client's source. Leave it off (the default) to keep the NAT-crossing hole-punch. 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, enrol the module's signing key: sudo mokutil --import /var/lib/shim-signed/mok/MOK.der, reboot, Enrol MOK at the blue screen (or disable Secure Boot). On Fedora, follow RPM Fusion's Secure Boot steps.
• After a kernel update the module may need a rebuild — reinstall the driver package.

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).

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).

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.

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.

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.

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.

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.

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.

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), 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.
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.

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.