On my system 3 machines... if you have the rubber ring too tight. the sling will turn itself off. There is a "feature" where it keeps it from machine gunning and if it does it a few times, it will turn the coil off. Check to see if the ring is too tight or the switch is gapped wrong. Adjust as necessary. If the switch is shorted together or the ring too tight and it fires a few times in a row it will disable it for the game. Hope this helps.