A few months ago I began to have an issue while playing on the lower PF on AcDc premium.

whenever I would be in the lower PF the kicker would fire constantly (well only when I was hitting a flipper) if I didn't hit anything, the kicker worked fine just kicked the ball whenever the ball was in the trough. But when I was playing the ball not in the trough I would hear the kicker firing constantly.

So I have several good Pinside friends and they were all good enough to help me out. First people said it sounded like an opto problem so we re-flowed them and finally after talking to Stern support we ordered new opto and new opto board. The weren't sure either but this was what they thought.

Still nothing, then I had another Pinside friend over thinking we were overlooking something. But still it was the same thing. we were thinking maybe a vibration or a lose connection or maybe a bad driver board. Anyway we were stumped. Then we had yet another Pinsider this a pinball tech and electronic tech. We were on that problem for hours, couldn't find what. Only clue was that the error didn't occur when we were in test mode, everything was ok, but whenever we played the lower PF we got the constant kicker.

Finally, the last tech said (as he was leaving almost as an afterthought) that it sounded like a software error, he didn't know what but suggested I reset the factory defaults or maybe load the latest code (I'm still on 1.65 because my song modifications).

I just reset the settings to factory default and the bug went away, everything is working fine.

The last settings I changed, were that I lowered the voice and raised the music settings. And probably that caused the bug. I can't even recall what the settings were.

Maybe I'll fiddle around with the sound levels and see if this is re-producible but I'm just glad to have the pin back in ship shape.

I'm thankful for all those who helped me. But I'm so puzzled how such a thing like that happened. It's very bizarre.

I didn't say it was a Stern bug, a program bug that (it appears) was only influenced by a setting in the menu (my case was voice or music volume level). It just seems so unrelated in my mind and a lot of other people too were thinking along the line of a hardware bug or even a mod that might have some electrical feedback to the kicker mechanism.

I mean the modified code works fine except in this one instance I described (I mean the music level change). I never even considered that a menu setting could cause this type of behavior, as the menu setting is not related to the lower PF or the kicker.

Just goes to show me that these games are extremely complex. We much prefer when there is an obvious problem like I need new opto or something like that. This was maddening to diagnose.