I'm no genius or a modern pinball owner but generally when something like this happens in code (and not bad RAM, hardware, etc. not letting it write to the credit counter and so on) I would assume the audits got corrupted in the memory and when it tried to +1 the audits for each credit/coin, it freaked out because it couldn't add 1 to 0x0f0f0f0f0f111111BBBC, etc. (and likely reset as a failsafe rather than freaking out)