Just bought a second Black Knight, what can I say..anyhow installed an MPU 327. Where to begin. She makes a lot of sounds now and one big lonnnnng continuous , truly annoying attract noise maybe? Can't get the drops to reset nor the slings. Flippers work tho . Cleaned most switches got the credit to work, going to post a picture of the back of the power supply thinking bad ground , looks like someone tried to do something back there . I am no expert.