I have Comcast basic cable connected to my Hitachi 57F710S through my TV's QAM antenna input and I'm having trouble with the audio sync on all digital channels. The audio is consistently out of sync with the video. Audio typically lags behind the video, but the lag time varies and I have on rare occasions seen the audio ahead of the video. I contacted Comcast and they referred me to my TV manufacturer, so I contacted Hitachi and they sent me their latest firmware update. I applied the update and it had no effect, so I called Hitachi back and they said that since I'm not experiencing the issue on analog channels that it has to be an issue with the cable company. I followed back up with Comcast and they indicated that they do not support any method for receiving digital channels on basic cable so they can't support this issue. Does anyone have any suggestions?