If the problem remains even if you remove the speakers the TV has been magnetized, so it has a constant field. Consider degaussing your TV.
Speakers causing problems with TV
I have a pair of speakers sitting right next to the sides of a 32" TV. They have been in this position over a year and recently have been noticing color/tint distortion with the TV. I have tried moving them further away from the TV, but the problem remains. Has anyone experienced this problem? What can you do short of moving the speakers into another room?