We frequently hear audio stuttering using the Apple TV app. It may even occur 100%.
This seems to be the primary reason my wife hasn't asked me to switch to Channels and abandon Plex, which she has come to hate due to multiple daily Plex failures, both with the server and, especially, the Apple TV app.
(Unlike an iOS topic poster, I have not experienced audio stuttering with the iOS app.)
Are you listening through your TV speakers? I notice audio glitches, but only with AirPods, and only when switching to Picture-In-Picture, so I've chalked my issue up to an AirPods issue.
Describing your hardware setup would help others help. Without knowing this, there’s not much anyone can suggest.
There are lots of variables at play with AV setups.
Audio Stuttering here also when watching live TV on ATV 4k Gen 3, TVOS 17 but also happened on TVOS 16. If you back up a bit (rewind) then the stuttering goes away as long as the behind real time. Haven't noticed it on recorded material.