I just upgraded to Ubuntu 22.04 from 21.10 today. After upgrade, HDMI Audio setting is not playing any sound through TV Speakers. Video playback on Plex is also broken, stopping and starting and very jumpy. I assumed it was an issue with the upgrade, so I did a clean install of 22.04. Everything works as expected when using built in speakers, Plex video plays correctly and has sound. As soon as I change to HDMI audio output, I no longer get sound and playback on Plex breaks. This is a Dell 6540 laptop. I have swapped HDMI cables and get the same result. No issues with this laptop on 21.04 or 21.10.