i've been having these since two PP 2015 updates ago. it was doing it everytime i made a major scoot of clips down the timeline. i tried to isolate it to a certain area of the sequence, and it seemed like it was a couple pesky AE linked sequences. i took those out, same problem. i trashed prefs (holding shift/option at PP startup), but NOW it crashes when i first start PP! and by "crash" i mean the eternally spinning beach ball and "application not responding" when right-clicking on the app icon in the dock.
my only workaround right now is to go back to an older version from auto-save and see if i can keep working. cache has been cleaned, preview folders deleted. not sure what else to try.
thanks for helping out a bonehead!
FCS3 / Adobe CC
3.33 GHz 6-Core Intel Xeon Mac Pro
ATI Radeon HD 5870
...and a few TeraBytes o' storage
(then it's on to PetaBytes, ExaBytes and MosquitoBytes!)