Client shows game logo and plays sound, but no video

[keet77]

I'm trying to set up a computer as a headless Steam Remote Play host using gamescope.

If I stream a game directly from Steam (running the graphical client on the host) without gamescope (no command-line options in the Steam game setup), it works. However, if I use gamescope, then the client plays game audio but shows only the game logo and the loading circle at the bottom-right.

This is true whether I use gamescope in standalone fashion in headless mode to run Steam itself or run the Steam graphical interface and add gamescope in the launch options of a game (multiple games, using Stardew Valley as a test).

I've tried multiple computers and configurations:

Gentoo host and client (three different computers)
Gentoo host and Mint client
Gentoo and Bazzite (fresh installation) (each as host and client)
Gentoo/Bazzite host and Windows client

All exhibited the same problem.

These are some sample commands I have tried:

Headless:
gamescope -e --backend headless -- steam
gamescope -e --backend headless -- steam -pipewire
dbus-launch gamescope -e --backend headless -- steam

Launch options in graphical Steam on host:
gamescope -- %command%
GAMESCOPE_WAYLAND_DISPLAY=wayland-0 gamescope -- %command%
VK_ICD_FILENAMES=/usr/share/vulkan/icd.d/radeon_icd.x86_64.json gamescope --expose-wayland -- %command%
AMD_VULKAN_ICD=RADV gamescope --expose-wayland -e -- %command%
gamescope --expose-wayland --fullscreen --force-grab-cursor -e -- %command%
gamescope -W 3840 -H 2160 -f -b -g -R -e -r 60 --expose-wayland --disable-layers --debug-layers --debug-focus --synchronous-x11 --debug-events --debug-hud --force-composition --composite-debug --disable-xres -- %command%

The client log always looks similar to this: https://pastebin.com/qCCRWHhJ

The only problems I see in the client log (linked to above) is this, saying the frame loss is 100%. That's obviously not good, but it doesn't tell why it's happening, and searching for that message revealed very little.

Mon Dec 29 20:41:03 2025 UTC - Streaming session complete, average network time: 0.00ms, stddev: 0.00ms, 100.00 percent frame loss, result: poor

Does anyone have any ideas? Thank you!