Image on screen scrolls up continuously.

I am trying to make some portable handheld consoles. The first is a playstation one
. I purchased the following display screen http://www.amazon.com/gp/product/B0045IIZKU/ref=oh_details_o03_s00_i00?ie=UTF8&psc=1
When I hook the PSone up to it the Sony boot image looks fine and so does the memory card/ cd select screen. However, when I got to play a game, the video image continually scrolls up or down on the screen. What would cause the image to scroll when running a game, but not when the loading screen or boot selection screen are showing?

Any ideas?