Autofiring is a situation I want to distance myself from (after pulling the batteries) not try to fix. It's just too dangerous a situation to try and fix, and even if you could, there is no guarantee that it has been permanently fixed, and won't happen again, maybe during a time you won't catch it doing that.
If under warranty I'd return it, if not perhaps replace it. Honestly I don't know that setup and if it's one worth enough money (if the warranty is expired) to send it back to the manufacturer to see if it can be repaired, and that's really more for pretty expensive high end mods, if it's something more budget oriented and the warranty is over, replace it.
Best of luck,
Anna