I've got a Mata Hari I've been working on and have a strange problem. Very occasionally (like once in every 20 or so games) the game will fail to award bonus points when the ball ends. It cycles through the count down of whatever bonus was earned during play, but doesn't sound the chimes or award points. It looks just like how the game behaves when it tilts, but the tilt light is not lit when it does this. I've confirmed that none of the tilt switches are enabled, and there doesn't seem to be any pattern of input when the failure occurs.
Any idea why I'm not getting my bonus when I should?
Game has an Alltek MPU. Plays fine otherwise.