We've had nothing but good to say about our HD setup, Vip722 with the dual TV support. Just today however, when watching live TV or prerecorded stuff, the audio and video are out of sync, and sometimes the picture freezes on a frame and doesn't progress for a few seconds, only to freeze again and repeat the freeze/progress/freeze rotation. This happened once before, and we just walked away for an hour or two with it off, and that seemed to fix it. Doing the same today, after an hour or two it went back to normal. Any ideas what could cause this?