A very common occurrence on today's TV. It is not always a TV Fault. I have troubled shooted this problem with a receiver box. Cable or Satellite boxes may need rebooted. Pull out the plastic card that is inserted in the box. Unplug the receiver box for one minute. Plug box in, reinsert card. Power up. If this does not work call your service provider per 1-800 number, they can assist in a more thorough reboot. Thanks for asking, Matt of Martins TV Repair.