So I just built a Ryzen 5600g system. It’s doing the same thing. It will not output HDR correctly unless while playing a video I press “\” and then the system switches resolution it appears and it asks me to keep the setting. I go no and then it switched back and HDR is outputting correctly.
I also noticed even though I disabled mouse control in the Kodi settings. When I play a video I can see the mouse until I press the “\” and once outputting correctly I don’t see it.
Also should it be saying ff-hevc (sw) ?
I've also uploaded the Log
I can confirm this with an AMD RX560. Starting an HDR movie will not switch my TV over to HDR but if i then press "\", answer the resolution question, it goes to HDR.