Yes I have played that tape to a tv before and it sounds just fine. And yes, the audio and video are both in sync. I noticed that I have been having the problem every 5 minutes or more when it is capturing. When I play the capture in a video player, I still have the problem. I sometimes have things running in the background, but not usually. Antivirus...Do you mean is it normally opened completely or just running in the background like normal? I do normally get rid of junk files, but I don't defrag. Maybe I should try this?