Hello, we can't disable physical stabization so it is of course digital image stabilization option. About length it's lottery but usually the longer clip is the faster sound will rip. For example I've recorded some random clips with eis on, one 14 seconds long - sound stops at 12 second, and 24 seconds long - sound stops at 23 second. I also have one clip from 22 march when I've created first topic about this issue - it was 28 seconds long and sound stops there at 24. I'm using h265 codec.
Here's my first topic about this issue: https://zentalk.asus.com/t5/zenfone-8/zenfone-8-video-sound-clipped-camera-app-issues/td-p/362639
Here are some sample files recorded by me to test if this bug is still active (and one from march 22, when I've first issued this bug:
Here's my video settings in the camera app. (Polish language)
Ok, now i can confirm that it is stabilizer from camera settings, that break the soundtrack. It does that with back camera also, when it is enabled.
Back camera is hypersteady supported and with it, sound keeps working but if you disable hypersteady and using only stabilizer from settings, then the bug occur.