Sub not working. I just got a new Yamaha RXV-800 and the Energy Take 5.2 speaker system with the

Question

I just got a new Yamaha RXV-800 and the Energy Take 5.2 speaker system with the 8.2 subwoofer. The receiver has a sub-out and I have a monster cable connecting the sub. All other speakers work fine but the sub gets nothing but a slight buzz at best. With the receiver power off, I removed the RCA cable to switch cables and the Sub then gave a buzzing sound whenever I touched the open RCA connector. Does this mean that the Sub is bad or the cable shorted? I exchanged the receiver because I thought it was the output jack, but the problem continues with the new receiver too. Any thoughts? Thanks.