So 2 of the PF friends have received have issues.

1 had a bad opto in the trough
Easy fix.

But the second is strange.
If you lock 2 balls in the upper lock and 1 in the lower. It trys to add a 5th ball to the game.
If you have 2 balls in the bottle lock and 1 in the top, the same thing happens, it trys putting 2 more balls into play.
But since it's a 4 ball game and 3 are locked up and 1 is in play, it keeps trying to add another ball, every 3 seconds. As if a ball is not being seen by an opto.
But the optos all work in test mode.

Code issue?