I have been sold a diy built Motional feedback subwoofer that is distorting, plus lots of lose screws, HELP I think i've been conned, so its money back I hope. On the dual coil visaton drivers there is only the normal cable run to the terminals. Should there be another cable run from one of the dual coil drivers for the sensor to feed back to the amp or don't it work that way. THANKS CHAPS