I'm having a problem with the 3rd ball lock. It seems sometimes it can't figure out there is a ball in the 3rd slot. I check the opto and it both 1 & 2 opt register. They seem to trip with the reel rotates. What exactly tells it there is a ball present? No issues with 1 & 2, just happens pretty much when ball 3 is locked. It launches the other 2 balls but continually rotates but never drops the 3rd ball until it does a ball search.
Any ideas?
Thanks
Ed