AirPods 4 ANC distortions onyl with 3D audio + headtracking watching youtube

I randomly get a rasping noise on both headphones for about 1 second. Sometimes its every few seconds, sometimes twice a minute or so.

I could narrow it down to the very specific combination: 3D audio + headtracking watching youtube in Safari on macOS 15. Change any of these parameters and it goes away, and returns reproducably if I go back to this configuration.

I reset them, deleted personalized spatial audio, unpaired and repaired them, tried two different Macs, to no avail.

So I thought they were damaged and I bought a second set. These paired immediately to the Mac and - same distortions right away :-(