I've been having a very frustrating intermittent problem with my World Cup Soccer '94. At times, balls will randomly pop into the shooter lane. I'll be playing and then I can feel the solenoid for the ball eject half-firing and then finally it fully fires, ejecting a ball. Sometimes two or three balls will get kicked out. It's very random timing, sometimes half-way through my first game, sometimes not until the second or third. Other games it plays fine and no extra balls are kicked out. I've tested the opto trough boards and even replaced the emitter board, but the problem persists. No random switches fire during the switch test, and the balls don't seem to be getting stuck in the trough. I've kind of eliminated the trough optos as the problem as they seem to work fine. This leaves the opto board that the emitter and receiever connect to. I tried reflowing the board without success. I hear that the chips can go bad on this board - could that cause this type of behavior? Should I just replace the board? Any other ideas of what could be causing this? The intermittent nature of this issue makes it very hard to troubleshoot. Thanks for any input anyone has.