What causes a black and white screen with a checkerboard pattern?

My ps3 runs like it always did however the screen has changed. It has changed from color to black and white with a very light flashing pattern. The whole screen has a very small checker board design that moves from bottom to top. I can still watch movies and play games just like I always did. It just seems to cause head aches.

I did a small cleaning on the cover and I noticed the av connection had some play on the back of the game system. I also reset the audio/video by disconnecting everything except the power.

I think it might be the av connection being loose that is the problem but, I would like to know if this is the problem before I take it apart to fix it. Was that too much info...?