My TV has been doing some weird stuff. any help?

I have a 22' 720P insignia HDTV and at about 4 AM every night while it's off, the screen flashes a lot for about 10 minutes and it goes to a random channel like FX or Spike and the volume goes all the way up. this is creeping the **** out of me. Why the hell is it doing this? I've had it for about 3 years.