I have a 55" TCL Roku TV (55S405). When I play an MKV file with 2 channel AAC audio, every 10 seconds or so the audio drops out for a fraction of a second. It makes the content completely unwatchable. This only started happening after my TV updated to 10.0.0 (build 4195-3.0) a few days ago.
It doesn't matter if I play audio through my HDMI ARC sound bar or if I disconnect the sound bar and use the TV speakers. The behavior is the same.
Looking at Plex forums and Reddit, it looks like many people are experiencing the same issue.
Looks like this is a duplicate of https://community.roku.com/t5/Playback-Issues-Audio-Video-Power/Audio-dropouts-with-HE-AAC-on-Roku-M...
I've been having this exact same problem since the 10.0 update last week. I sure hope there's an easy fix coming for this.