Pull the audio cable from the sub does it still hum? if the hum goes away then you may have a loose or bad cable. If the sound is there with no audio input then you have problems with the amp in the subwoffer good luck and please posr back to us stewee
I've been using the reciever's line level sub output for my sub for about 8 years now. Just recently, the sub started to have a constant vibration/hum. What's strange is that it seems to be independent of the source signal going into the reciever, meaning, it will still hum even while I'm switching sources. What's even more strange is that if I tap on the top of the reciever with my finger, the sub's cone will thump along with it. It's almost as if the line level is putting out the reciever's natural frequency or somthing. The hum/vibration can get pretty loud/violent at times.
Does anyone think they know what could be the problem? Everything else with the reciever works fine and I'd like to salvage it if possible. Thanks.