Thank you very much, I have no idea that plex doesn't support AMD HW decoding. It's a pity!!!! You save me to do an orrible mistake. Seems to be a workaroud (https://forums.plex.tv/t/got-hw-transcoding-to-work-with-libva-vaapi-on-ryzen-apu-ryzen-7-4700u/676546/64) but I don't want to spend 750eur and use my huge plex library betting on a workaround.   So, I need to rethink my configuration. 😞