Ive bn given this tv to repair its powers up fine and the sound works ok, but the screen doesnt show any image it just stays blank. There is a little bit of fuzziness in the bottom right corner of the screen which when i press the menu button it dims and then when pressed again brightens back up! Apparently there was a loud pop from the backwhen the fault occured! Any ideas as to what this my be? Is it repairable? The set is only 18months old!