Right in the middle of my show, a black screen comes up and starts talking about why I should buy this floor model. My remote won't work, I can't turn it off, I unplugged it and when plugged back in, same thing was on screen. I called comcast and they said it was my tv--sounded like some program--been over 4 hours now and that is all I can get--this black picture stating why I should get a floor model. Is there ANYTHING I can do so I can get different programs? I can't even turn it off at the tv itself.