Can anyone advise how to fix this problem I'm having with this greyboy? I started to install a backlit screen and noticed that the contrast is all messed up. I have to crank the pot to see much of anything, and when I do, the contrast is not distributed evenly. There's too much being drawn vertically in areas where there are supposed to be many pixels, and not enough drawn where there are less supposed to be less pixels. Take a look at this video.
Batteries are good, other screens (entire front PCB to be precise) work okay. Changing games only manifests the problem in slightly different ways depending on how many pixels are supposed to be drawn at a time. Heating the strip below the screen doesn't do anything useful - all the lines are there, they just aren't being drawn correctly.
Maybe caps are bad? Messed up ribbon?
Any advice would be appreciated. Thanks.