My vintage machine just won't play ball. I plug into the mains, lights up and that's it. No sound except hmmm. Coins and tokens just go straight through to tray. Rear panel open or closed no difference. Powered off and taken mpu3 out turned it on and no difference. Turned off and replaced mpu3 no difference. Any advice would be much appreciated! Cannot seem to get it to reboot, sanity needs to return ! Thanks everyone