Furniture flashes

My gameplay technically works but theres this weird glitch where furniture and walls flash repeatedly even when I put walls down all the way. I have repaired my game multiple times, I even took all my mods out and it still was glitching. Im playing on mac, and no im not getting any last exceptions. It happens on any save. and Im not getting any crash files.

I havent seen anyone else with this problem so far, and this is the only problem ive experienced with the new update.