This is probably a little late & you may've replaced or repaired your issue by now, however, I was told by a technician friend of mine that "pixel burn" issues caused by over brightness, long pause or some images can be "wiped" in much the same way as the old etch-sketch toys. ie switch to analogue & select a non channel so the screen displays "snow". leave this for a few minutes & it will have refreshed all of the crystals in the affected area. I hope this helps!
Si Sutton
July 2009