The RCA connector on the rear of my Energy 10.3 sub is broke and spins freely. The previous owner had a locking sub cable connected and I should have known something was up when he delivered it to me with the cable still connected. Since it's my problem now I want to repair it myself and and upon investigation (I removed the rear plate from the sub) I noticed a grey wire (which was part of a bundle of multicolored wires) that had been disconnected from the rear of the RCA jack (gold hex nut with black liquid tape applied). I stripped grey wire and rear of RCA connector of black liquid tape and soldered grey wire to the rear of the RCA jack.and when I reconnected everything all I got was a constant humming sound that increased/decreased as I turned the volume up/down. I'd like to try and replace the RCA jack and bundle of colored wires with connectors but I cannot reach Energy as their phone system is not accepting calls. I've attached a pic prior to solder. Also not sure what the small wire is between the rear of RCA jack and tab on the left of the jack.
