I just had this problem a couple days ago. I had a friend come over to my house for the first time and saw my pins and wanted to play naturally. We started playing on my Space Shuttle and that machine is very basic.. We then switched over to my Centaur II machine, I went first and my friend watching me play noticed that I was able to nudge a ball back into play. I explained to him that this machine was designed for a skilled player to lightly nudge the ball back in play. I stepped away to grab a beer and not but 2 mins later I walk back and find my friend smashing into my centaur looking like he was trying to flip it over! The game proceeded to 'blackout' and restart itself. This problem would then reoccur every time I played it until I looked into the problem and fixed it. Needless to say my friend is no longer welcome in my home.. Atleast for now. But he lost his pinball playing privliedges.