Quoted from TopMoose:To add to the mystery, I switched the setting to 3-ball play and it still counted up to five balls and wouldn't end the game. That makes me think the problem is in the ball count unit, but advice would be appreciated
You are right. The Ball Count unit is most likely the problem. From out of adjustment, wires broken off, the switch stack on the backside could be out of adjustment. The last Gottlieb I bought had the rotating part attached 180 degrees off.