I think I have a bug to report. Apple TV 4K (A1842, tvOS 13.3.1), Channels DVR Beta version 2020 (3.18.146) - although this was happening in previous versions as well.
I have a channel tuned and playing audio through my receiver. If I then connect my Airpods via long press on the "Apple TV App/Home" and select the Airpods for my audio source. The audio will come out in only one ear or louder in one ear. If I untune the channel and go back in, the audio is normal. I have not noticed this in other Apple TV apps.