Quest3 - Head rotation problem in Unity play mode

When connecting Quest3 via airlink to Unity (play mode), head rotations are not visible in the headset. The tracking works ok in the unity desktop game window, but in the headset is no tilt. It seems the scene is always centered. Eg. a cube will not tilt when I tilt the head. Tracking the head sideways and up/down works but rotations seems to be deactivated. Maybe there is a kind of billboard function that prevents tilt rotations? Any suggestions?