Did you managed to solve this? It works for me when running the docker exec -it command, but same error when using transcoding via Plex in the log.
Error in plex log:
Oct 08, 2023 20:49:00.913 [140475409365816] ERROR - [Req#2c7/Transcode/8dc2d641ca5dca52-com-plexapp-android/2b16246b-cb38-4288-bea6-2cc578025495] [AVHWDeviceContext @ 0x7f50d6ba6380] libva: /config/Library/Application Support/Plex Media Server/Cache/va-dri-linux-x86_64/radeonsi_drv_video.so has no function __vaDriverInit_1_0
Oct 08, 2023 20:49:00.913 [140475411475256] ERROR - [Req#2c8/Transcode/8dc2d641ca5dca52-com-plexapp-android/2b16246b-cb38-4288-bea6-2cc578025495] [AVHWDeviceContext @ 0x7f50d6ba6380] Failed to initialise VAAPI connection: -1 (unknown libva error).
Oct 08, 2023 20:49:00.913 [140475462847288] ERROR - [Req#2c9/Transcode/8dc2d641ca5dca52-com-plexapp-android/2b16246b-cb38-4288-bea6-2cc578025495] Device creation failed: -5.
Oct 08, 2023 20:49:00.913 [140475409365816] ERROR - [Req#2ca/Transcode/8dc2d641ca5dca52-com-plexapp-android/2b16246b-cb38-4288-bea6-2cc578025495] Failed to set value 'vaapi=vaapi:' for option 'init_hw_device': I/O error
Oct 08, 2023 20:49:00.913 [140475411475256] ERROR - [Req#2cb/Transcode/8dc2d641ca5dca52-com-plexapp-android/2b16246b-cb38-4288-bea6-2cc578025495] Error parsing global options: I/O error
Running via docker exec:
docker exec -it -e LIBVA_DRIVERS_PATH=/vaapi-amdgpu/lib/dri -e LD_LIBRARY_PATH=/vaapi-amdgpu/lib plex \
/lib/plexmediaserver/Plex\ Transcoder -hide_banner -loglevel debug -vaapi_device /dev/dri/renderD128
Splitting the commandline.
Reading option '-hide_banner' ... matched as option 'hide_banner' (do not show program banner) with argument '1'.
Reading option '-loglevel' ... matched as option 'loglevel' (set logging level) with argument 'debug'.
Reading option '-vaapi_device' ... matched as option 'vaapi_device' (set VAAPI hardware device (DRM path or X11 display name)) with argument '/dev/dri/renderD128'.
Finished splitting the commandline.
Parsing a group of options: global .
Applying option hide_banner (do not show program banner) with argument 1.
Applying option loglevel (set logging level) with argument debug.
Applying option vaapi_device (set VAAPI hardware device (DRM path or X11 display name)) with argument /dev/dri/renderD128.
[AVHWDeviceContext @ 0x7f911e43f0c0] libva: VA-API version 1.17.0
[AVHWDeviceContext @ 0x7f911e43f0c0] libva: Trying to open /vaapi-amdgpu/lib/dri/radeonsi_drv_video.so
[AVHWDeviceContext @ 0x7f911e43f0c0] libva: Found init function __vaDriverInit_1_17
[AVHWDeviceContext @ 0x7f911e43f0c0] libva: va_openDriver() returns 0
[AVHWDeviceContext @ 0x7f911e43f0c0] Initialised VAAPI connection: version 1.17
[AVHWDeviceContext @ 0x7f911e43f0c0] Format 0x3231564e -> nv12.
[AVHWDeviceContext @ 0x7f911e43f0c0] Format 0x30313050 -> p010le.
[AVHWDeviceContext @ 0x7f911e43f0c0] Format 0x36313050 -> unknown.
[AVHWDeviceContext @ 0x7f911e43f0c0] Format 0x30323449 -> yuv420p.
[AVHWDeviceContext @ 0x7f911e43f0c0] Format 0x32315659 -> yuv420p.
[AVHWDeviceContext @ 0x7f911e43f0c0] Format 0x56595559 -> unknown.
[AVHWDeviceContext @ 0x7f911e43f0c0] Format 0x32595559 -> yuyv422.
[AVHWDeviceContext @ 0x7f911e43f0c0] Format 0x59565955 -> uyvy422.
[AVHWDeviceContext @ 0x7f911e43f0c0] Format 0x30303859 -> gray.
[AVHWDeviceContext @ 0x7f911e43f0c0] Format 0x50343434 -> yuv444p.
[AVHWDeviceContext @ 0x7f911e43f0c0] Format 0x41524742 -> bgra.
[AVHWDeviceContext @ 0x7f911e43f0c0] Format 0x41424752 -> rgba.
[AVHWDeviceContext @ 0x7f911e43f0c0] Format 0x58524742 -> bgr0.
[AVHWDeviceContext @ 0x7f911e43f0c0] Format 0x58424752 -> rgb0.
[AVHWDeviceContext @ 0x7f911e43f0c0] VAAPI driver: Mesa Gallium driver 22.3.6 for AMD Radeon Graphics (renoir, LLVM 15.0.7, DRM 3.49, 6.2.16-3-pve).
[AVHWDeviceContext @ 0x7f911e43f0c0] Driver not found in known nonstandard list, using standard behaviour.
Successfully parsed a group of options.