My Sharp Aquos TV has a strange black line on it, what do you think is causing it?

[Jonathan]

I have a LC-46XD1E tv, and it has a line of black that runs half way across the screen. Sometimes the line turns blue, depending on what the screen is displaying at the time. The line displays on all inputs.

My guess is that it's either a load of dead pixels (which I'm hoping it isn't) or a bad controller board. If it was a line of dead pixels though, why does the line disappear on that one test pattern? (shown on the video)

Thanks in advance

Here is a video of my problem:

http://www.youtube.com/watch?v=2VT5eNwKbFk