As the title says, the reason is that the screen has got a tennis ball sized mark on the inside, at first we thought is was down to the position of the set, and the light coming through the blinds, so the other day we tried it in a different position and the mark was still there. So on the phone i got to Curry's, expecting to have a hard time, like i got from Comets. They arranged an engineer to visit, he arrived 2 days later, saw the blemish, got on the phone and arranged authorization for a replacement. Went to Curry's today, they have them in stock and are delivering the new set next Saturday. Damn good service if you ask me.