lol you cant even spell Dynex correctly even though its written right on the TV itself and yeah buy a different TV those are junk and made to break quickly. Take it back to bestbuy if you have issues since Dynex is their own brand.
Since I have no clue what the issue is, I'm going to post my thoughts. I used to be Samsung and RCA certified, and for the cost of labor and parts, you'll be better off just buying a new TV. Most shops will charge $50 to $100 just to look at it.