World locking not working as expected. Virtual content changing alignment regarding the scene

Hi there. I just cant seam to figure, how i can ensure, that my virtual content is always aligned with the real world scenario. after restarts the orientation of the generated room is sometimes different and sometimes not.
I tried:
Reducing the room index in the mruk to 0
enable world locking
parenting all virtual geo to the tracking space

Its all on PC VR in unity