I had a game that the colors would not look right on it at all for some reason. It had a K7000 chassis board and I tried two different ones that are known to be good.

Here is what it looked like:

The fix was finally I found out I needed to adjust these things I am pointing at with my flat head screw driver (I don’t know the technical term… magnetic beam adjusters?)

Here is what the Ms Pacman screen looked like before:

Here is after some adjusting (still some to go on the right)
I was able to do this with the tube on HOWEVER be very mindful where your hands are
I AM NOT RESPONSIBLE FOR ANY DAMAGES SO DO THIS AT YOUR OWN RISK

Maybe other wording to describe the issue:

foggy coloring
intermittent colors
rainbow color pattern