Magnavox 19& HDTV review: will not power on/shuts off -on 1

I purchased a new Magnavox LCD TV (Model# 19MF337B/27 Serial # BZ5A0745330212) in April of 2008 from BEST BUY, of Annapolis, MD. I was naturally hoping to have years of trouble free use from the TV as Magnavox has a fine reputation.

After approximately 1 year of trouble free service a problem with the TV developed. It has become extremely difficult to turn the unit on. It shuts itself off repeatedly and then turns back on for a few seconds This process can last up to 20 minutes each time the TV is turned on.

Now the sound won't come on, even when the picture remains on.