My subwoofer recently started to have a constant "hum" coming from it. I've had the sub for about a month and I haven't noticed it until recently. The best I can make of it is it is receiving a constant signal telling it to emit a sound, as the green power light in the back stays on even after I turn the receiver off (it does sometimes eventually turn itself to sleep mode (the light turns to red), but not for a while, and sometimes not at all). The "hum" actually gets louder when I turn the receiver off. The sub is the EP350 and I have it connected to a JVC receiver using a subwoofer cable I bought at Radio Shack.

Any thoughts on what might be causing this? Thanks in advance for any help you can provide.

http://www.axiomaudio.com/tips_eliminate_hum.html

Hi Skimble,

Hum problems and "ground loops" are really annoying, but all of them can be solved. In addition to that link to my article on hum problems, here are some updates and links to two inexpensive ground-lift transformers, either of which, depending on the source of your ground loop, will solve the problem.

Cable systems are seldom at "zero ground potential", which means you'll get ground-loop hum when you integrate any audio-video gear with a cable-TV feed.

Try one of these video ground isolators and install it in-line with the cable before it enters your set-top cable box:

http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=180-075

Did you try disconnecting your subwoofer from the coaxial cable connecting it to your JVC receiver? If so, did the hum go away? If it did, you could try one of these from Radio Shack, which goes between the subwoofer and the coaxial cable from your JVC a/v receiver

http://www.radioshack.com/search/index.jsp?kwCatId=&kw=ground%20isolator
&kw=Ground+isolator

I would first try the in-line video ground isolator from Parts Express.

Regards,

Link1

Link2

Thank you for the advice and the links. I've printed everything out and will try to get rid of my hum over the weekend (and hopefully succeed before my Super Bowl party to show off my newly finished basement with my great new Axiom speakers).