Trouble with Moonlight app streaming to LG webOS : worked 6 months but now connection unstable & black screen

[rems1989]

Hi everyone,

I’m running into a very inconsistent issue when streaming my Windows 11 PC with apollo (fork of Sunshine) to my LG C4 TV using Moonlight (webOS).
The setup worked perfectly for about 6 months at 2K / 90 FPS with high bitrate.
Around 2–3 weeks ago, the issue started without any clear change on the PC side (possibly after a webOS update).

Symptoms:
•    Moonlight on the TV shows “connection unstable” with a black screen
•    Behavior is inconsistent and unpredictable :

• Sometimes nothing works at all with black screen
• Sometimes 2K / high bitrate work or not
• yesterday 2K didn't work but lowest resolution (1280x..) worked

•    Streaming to my phone works fine, so the host PC and network seem OK

What I’ve tried:
•    Clean reinstall of Moonlight on the TV and Apollo/Sunshine on the PC
•    H.264 only (no HEVC, no AV1, HDR off for testing)
•    All bitrate / FPS / resolution combinations
•    Ethernet and Wi-Fi
•    Different Windows display modes
•    Virtual display disabled
Setup:
•    Host PC: Windows 11, NVIDIA GPU (RTX 3070)
•    Apollo installed on PC
•    LG C4 TV, webOS 10.2.2, sideloaded Moonlight client (1.6.36)
•    PC and TV tested on both Ethernet and Wi-Fi (2 gbps internet speed on my computer)
•    Streaming to other clients (android phone) seems to work reliably

Feel free to ask me any information needed
Thanks for your help