aww too bad someone close to you or yourself does not have another dmd to try or dmd controller board. I bet its the ram on the dmd controller board. If your not going to repair it swap the controller first.
Seen that lots. Same as bad caps but that usually causes rolling. Cables are number 1 and as you tried reseating them along with replacing them so we can rule them out.
Little tip......make sure your dmd controller is 100 percent before plugging in your new display!
no sense potentially hurting a new display..
Good luck and cheers

This is exactly why I suggested replacing the boards as opposed to using the test menu because once display issues get bad its tough if not impossible to read . Good on you for fixing it. Color dmd's are amazing.

As mentioned above...Your original controller merely needs a ram replacement and a 7 - 10 dollar high voltage rebuild and its good to go. Some dmd's make noise with certain power supplies. If you rebuilt the original I bet it would be much quieter.
Time to play. You'll be back! Sorry had to say it.

as for your Ball / switch issue check the switch test and see what does or does not work. Use the ball to test switches as your finger is inaccurate. You will find your problem in moments. As mentioned above the internal software and tests are your friend and should be your go to when you have a problem.
Let me know what u find.
Cheers