Yeah, it's new. I always make my own shadows, but noticed it was lagging on sync so i rechecked everything and caught the built-in shadows. Maybe if you have a shadow on your hands already, then you neglect to click off the shadow effect, it seems like it's doubling it and the code is freaking out, like "TWO shadows?! Whaaaaa?!"
Might have just been me, might have just been a one time thing, but thought i'd throw it out there in case others are having issues.