Hello, for a while I have been able to view youtube videos full screen. But a few weeks ago, with no real change on my end, watching any youtube video or I guess flash video in a window.. it flashes periodically. Very quickly. When going full screen it becomes like a stop animation film. I haven't done anything other than regular updates. No hardware changes. Any help? 
EDIT: I should add that audio is normal
EDIT: I should add that audio is normal