MBP screen distortion problem

Recently the screen on my non unibody MBP has become distorted. I can still see and read everything fine but the colors go wonky and some color gradients look like they're shaking. If I hold the screen portion of my laptop just right it'll go back to normal but as soon as I let go, it becomes distorted again.

Does anyone know if this is just a cable issue or something bigger? Also any idea on how much it'll cost to repair?