Triangle with cs6

Hello,

I've upgraded to AE cs6, and now I am having this triangle when I'm working with files showing up just sometimes... It is not there when file renders, it is just there for like a second then it's gone-so fast I cannot even take a screenshot.

I don't have any plugin installed yet, so what might be the issue? This never happened with cs 5.5

Thanks in advance,

I managed to take screenshot

here it goes