Sound out of sync

[gluk147 4]

Hi everyone.
Any ideas what the problem might be?
Emby Server version 4.10.20.
For playback, I tried the Emby Android and Emby for Android TV apps—the latest versions from the Google Play Store.

I tested about six different movies; all used the AV1 video codec and Dolby Atmos TrueHD audio.
In all cases, the streaming boxes were connected directly to a Samsung HW-930F soundbar.

The boxes I tested were the Xiaomi Mi Box 3, Ugoos SK-01, and Homatics Box 4R; the problem was the same on all of them. Between the 55- and 65-minute mark, a severe audio-video desync occurs (a lag of about 2 seconds).
If I watch the same movies on the Google TV Streamer, there are no such issues—though that device doesn't output TrueHD audio.

The problem only occurs in the Emby apps; everything works perfectly via Vimu and Kodi.

I checked the server logs, but there are no errors.