Picture comes on for about 3-5 seconds, then goes to black screen, still has sound. Tried to go to MENU but with black screen cannot tell where I'm at on the menu. TV is conneced to cable box and when it comes on for the few seconds that it is on you see the channel #3, but it also says AIR, and I think it should say CABLE, but can't change without seeing the MENU items. Had TV about a year and don't know what occurred to change from CABLE to AIR. Did I hit the wrong button on the remote. Anyone else have this problem and if so, how did you correct it?