Ambient occlusion ceiling wierdness

'Got the same problem in BL:2 and BL TPS
Turnig On “ambient occlusion” makes some strange lines appear.
It looks like some static grid on a ceiling and any surface I look up on.
All this shadows make the game look much better, so I’d like to keep this function On, but after an hour of playing I’m starting to see this lines even in real life :dizzy_face:
So is there a way to get rid of this evil net keepin my game lookin pretty?