I've recently seen this but not found the source yet. If you've nvidia 302.17 installed, play a video and start a fullscreen effect (present windows) The video will show buffer errors (it's really weird, the video buffer from n frames ago is shown) -> we got to figure whether that's our fault or nvidias, whether it's in opengl or the xv texture adapter. Flipping seems to have an impact.
*** This bug has been marked as a duplicate of bug 304375 ***