My HD TV is really cloudy, and only fixes itself after about an hour?

I have a Sanyo HD TV that was given to me this year because it most of the time when you turn it on, it goes to a completely streaky screen, with audio normal. You can see some color from the feed, but cannot see any shapes. Most of the time, it fixes itself all of a sudden after a given time, which seems completely random...sometimes 5 minutes, sometimes 30, however today it will not fix after a few hours.

Anyone know what the problem is?