HomePod No sound issue

[sdp77]

I have two HomePods mini connected to an AppleTV, all devices updated to the latest firmware.
When playing a movie purchased from iTunes, no problem. When playing home videos, there is sound for 5, maybe 10 minutes and, then, it's gone. If I pause the playback and restart, the sound is back but for shorter periods of time. What gives?

 

[sdp77]

Nobody else encountered this issue?

 

[sdp77]

I may have found the cause of my issue: If the soundtrack is at a high rate (over 600 Hz), I get this issue with the sound dying after several minutes of playback. If I keep it under 600 Hz, no issues.