I just installed some new speakers in the door and my Sirius radio that I use, plugged into the cigarette lighter has some massive hum. I thought I screwed up the speakers so I was pissed at first. I then tried a CD and the radio and no hum. It is really bad. Any one else have this problem? I may just hardwire it and that should put an end to it.

Thanks,
Art

 

hardwire ftw... did you try both plugs?

 

yep, same problem on both.

art

 

If you're using an FM modulator, its more than likely that.

 

my bad. no fm modulator. I have it going straight into the aux on the headunit. When I hook up an ipod there is no hum. When I leave the sirius on and go to like CD or FM then there is a popping sound on the speakers. If I turn off the sirius then it goes away.

 

There is a bad ground in the cigerette lighter i have the same problem,
but not with xm reciever.

 

Just from personal experience with a lot of stereo installs.....generally anything that hooks up to a deck that uses a "headphone" style plug, will cause a hum if it is powered by the vehicle.....things like ipods that are battery operated wont cause a hum because it is actually the power source (battery/alternator) from the car that causes this hum....most times it has nothing to do with a bad ground.....the problem with the headphone style plugs is that they are not shielded like an RCA is....very difficult to get rid of the humming from equipment that has these plugs.....sorry to say

 

Well my cable is shielded. Shielding is used so the cable itself does not pick up any harmonics from outside of the cable. For instance if the cable was picking up interference it would still be bad with the ipod, since the battery and alternator are still running and the cable itself is causing the problem. Either way, I hard wired it up and the "hum" is gone. Much cleaner install and I got my cup holder back!!

Thanks,
Art

 

Shielded cable can still pick up interference...aka ground loop. There's a part you can buy which will filter this out though but it's been years since I've done a car stereo install, maybe this place will have your answer?

http://everything2.com/index.pl?node_id=1396881