A few months ago, Rottendog made a few design changes to their very popular MPU327. Two things changed. The switch matrix driver changed from a 25V driver to a 100V drive, and the switch matrix connectors moved away from the mounting holes to minimize shorting in the backbox. So why would either of those things cause a sudden increase in reports of the board not working in Black Knight, and Black Knight only apparently? Problem is, I sell a ton of these boards, but I never know what game it's going to be installed in. As reported by @lavmech1, the symptoms are 1: No background sounds and 2. No 2nd ball. I actually have this report but on a 1st version of the board also in a Black Knight, so I am suspecting that it's something else. So we need your help. If you have a Rottendog MPU327, could you please post if you have a -1 or -2, what game, and specifically if you have a -2 working in a Black Knight. Your time is much appreciated to figure this out. I myself will be trying to set up a Black Knight I own to try it.