i have S2000 and when i got the machine there was no enhanced board ,but there were the connectors for it..i got the board and installed it ..There was no hum before i put the enhanced board on it ,but when i put the enhanced board on the board there was a hum out of all the speakers...i also noticed that when the lights behind the reels light up the humming stops, but comes back when the lights behind the reels stop flashing..It will play the enhanced sounds fine..the board came out of another machine and there was no hum..I was reading about the wires behind the reels as a possible issue, but it stops when the lights flash behind the reels...any thought would be helpful....thnks