Game plays great, display works, red LEDs flashing on both the sound and auxilary sound boards but no sound, just a full time hum, that never changes. I think I have tracked it down to the auxiliary sound board as I have noticed that when I hook up the A20J1 connector all of a sudden the A5 (auxiliary power supply) board gets warm- specifically the VR-1 regulator...toasty. Anyways, as long as I leave the A20J1 disconnected everything works great (except the sound) and nothing gets hot. Anyone have any ideas about what to check next, possible causes of the problem, or how to fix the situation, thank you all in advance.