I have a paradigm PDR10 subwoofer and is not working properly. When I was moving the extension cord it was connected to, I heard a crack from the sub. Could I have short circuit the woofer? I performed the test tones from my Denon 3300 avr receiver and have to push it 10 db in order to hear it but it wasn't loud enough as before. If I did break it, where can I bring it for repair? Thanks.