Clearly it's caused by gamma rays interacting adversely with the silicon of your CPU.
It's been a long day - that made me laugh - much needed!!
Yeah sorry, I know it's a really vague question. The problem is I can't post a video of it as the problem doesn't seem to be visible in the video when it's been recorded - even though I can see it clearly with my eyes (on the actual device it's running on)
I'm gonna do as you suggest and try to log out which animation frames are showing and when... might give me some insight into what's happening.