I'm not sure if I'm posting in the right place. If not, I apologize. I've been having this terrible, loud hum coming from both my subs. After connecting and disconnecting different components, I was able to determine that the culprit is my PC. I'm connecting the output of the sound card to my Outlaw 1050 receiver in order to listen to MP3s on my system. The cable used has a headphone jack on one end and two RCA jacks on the other end. When I removed the cable from the sound card output the humming stopped. Anyone know why this is happening and how to fix it? Thank you in advance.