First time pinball owner with a weird problem on my The Addams Family machine. Randomly, but occurring more often in the past few days, the ball being played has been seen by the machine as drained/lost somehow - although the ball is definitely in play. The game keeps playing (no feature total displays etc.) as normal although a ball has been lost (if playing single player) or either moves to the next player (if playing multi player).

I have got a few mods on the machine, so to eliminate that being the issue (power related) I have ordered a power daughter board from rkahr - but whilst I wait for that to come in the mail I thought I might throw this out to the gurus on this site who might have come across this problem before just in case it is something other than power related. Any ideas?

Thanks guys; you're right!

I never noticed that sometimes the ball would get popped to the plunger and the ball behind it would not follow to become 'the next cab on the rank'. I can here a faint clicking but on closer inspection I could not see a solenoid helping push the rogue ball so I presumed all was normal. This however was causing the issue - the next ball has to be ready to be ejected to the plunger or I get the drain/missing ball problem.

The switch edge test for the trough switches were all okay.

To fix I just bent the first wire that leads to the first ball (right side) sensor trough so the second ball would flow freely into that spot. So far so good.

Although I wonder what that faint clicking sound is coming from...; anyway cheers for the heads up, lesson learnt that some problems are as simple as observing a bit more (and giving a 30 year old machine some TLC!!).