Picked up a Zaccaria Pinball Champ. The sound was working when I picked it up, but now it is not. The connector seems a little flaky, but I can position it so that the led light on the sound board is steady on. When I hit the test button, the led flashes four times which I think is normal. When I get the connector in the right position, I get a thump kind of sound like when you connect a speaker terminal. The wires to the speaker are solid. On my Time Machine, I had to replace the sound amplifier on the sound board. Amplifier looks ok and the thump sound makes me think it isn't the amplifier. Any ideas appreciated.