Hardware transcoding does not work when HDR to SDR remapping is enabled

[KyleD324]

I had the same issue on 20.04 last month. Turns out the latest intel compute runtime update broke HDR->SDR hardware transcoding. It needs to be downgraded. See the linked post and thread below.

4K HDR Hardware Transcode

If you are using Intel iGPU : Latest compute runtime broke HDR Tone mapping on Plex Solution : Downgrade compute runtime drivers to 21.49.21786 Install these on your Plex container and test. It worked for me