Television Powers Off While Watching

Question

...it then turns right bcak on if we hit the power button (or stays off if we do no). Happens randomly. It can stay on for hours and not turn off or be on for 5 minutes and turn off. As you can imagine, it's frustrating. Vizio support not helpful as I'm not under warranty.No other problems with this 1.5 year old set.Thank you for any insight. B