I have installed polulu firing boards in my boat. The board that is controlling the stern gun has failed catastrophically twice now (sparks and small flames). The board that controls the bow gun works perfectly. Solenoid triggers as fast as I press the stick. Both boards are wired up the same. The only difference between the two boards is that the bow gun, which works properly, has a signal inverter on it and the stern gun does not. Side note, I have not cut any of the wires from the receiver and am using power from the main batteries to run the entire system. Not sure if that helps at all.