720p "shifted" on a Motorola DCT6208

Comcast just updated their menu system (Balto, MD) and before the update, 720p (my display's res) simply didn't work. It would simply flash every few seconds with strange reddish lines when I select 720p in the set top box's menu. 1080i, 480p, and 480i worked fine.

Now after the update, 720p now works, but the picture is way shifted to the right. The other resolutions work fine as before.

Any suggestions?

Thanks!