I just got back from one of the houses that I was running into this problem and I discovered how to solve it. I put the cable box into an HD setup mode that I had learned of from another post on this site{turn box off and hold guide and info on the front of the box}. It then askes what size the TV is 4 by 3 or 16 by 9. After I entered 16 by 9 all the standerd def channels that were normaly 4 by 3 with bars on the side were streched to fit the screen. The HD channels were not zoomed in. Then in the settings menu I made sure that the picture was set to normal and not streched. I hope this helps anyone that may have been running into the same problem.