Have a mid year MBP 17" and have been very happy. For the last week I noticed that when I enlarge any video stream to full screen, the lips do not sync with the audio. I tried disabling automatic switching of the video card and everything is normal when I enlarge the video. Should I just leave it on manual and live with the power drain or is there a way to resolve this. I loaded clean my mac a few weeks ago, could this be the culprit? Thanks in advance for any insights.