None of the Solutions steps in the "Solutions" area worked for me. I have a Sony 42" and have been through every setup option for the cable box and the TV. I've looked at solving this off and on over the last 6 months.
You can stretch and zoom SD or HD programs by pressing the # key on the remote control.
Also just to ask how is the box connected to the tv? There have been a couple of other postings I believe on this same issue with the same box. It may be the signal coding from the broadcaster not getting decoded correctly.
Over the weekend, I noticed the problem - during a baseball game in HD, the score display in the upper left only showed the visitors half of the display. The same problem was visible on the Weather Channel - graphics along the edge were only partly visible.
I tried all the aspect settings - they made the problem worse (including 4:3), as none of them make the source image smaller.
My first thought was that Comcast made some change, but I reviewed my settings in case I accidentally changed something. So, I rebooted the DVR - same problem after.
Current display related settings are:
DVR: Cisco RNG200
Menu>Setup>Screen Position Setup: the arrows are centered on the screen
BTW, the HD Zoom button on the remote has no effect
Menu>Input/Output Assign>Monitor Out>Resolution: Auto
Menu>Source Setup>Picture Adjust>Wide Mode: Auto
Menu>Source Setup>Picture Adjust>Picture Mode: Direct
Menu>Picture>Picture Mode: THX
Menu>Picture>Aspect adjustments>Screen format: Full
Menu>Picture>Aspect adjustments>HD Size: 2
The “FULL” and “2” settings displayed the most picture area
Again, the various aspect settings neither fixed nor improved the problem.
Before I call Comcast (sigh), does anyone have any ideas to try?