So I decided to spring for the more expensive Wei-ya universal with the remote board, instead of the sub-$60 chinese clone I was using before. But it seems I still have the same problem where brightness/color shifts depending on what's being displayed. Does it on all Jamma boards, I even input RGBs into the Chassis directly, bypassing the Jamma harness and it was still doing it.
Found a consistent way to display the problem I have.
Found a consistent way to display the problem I have.