WellThen

I've searched quite a bit, and haven't seen this problem. My 2004 RX-8 was purchased from the original owner in April, and he had installed one of the IPOD Aux-in kits, which plays through the Tape input. I've just purchased a portable GPS/MP3 Player, and when I power it through the cigarette lighter sockets (either one) I get this intermittent popping and buzzing through the AuxIn. This happens even if the engine is off, in accessory mode. If I power it from a stand-alone car charger that has a cigarette lighter port, I get no noise.

All the posts I've found have been about alternator whine, which changes with RPMs. But since mine happens when the engine is off, I'm not sure if a ground loop interrupter will help. Anyone else experience this problem, or have any suggestions about what I need to do before I tap the cigarette lighter power line for a more permanent installation?

Thanks...

Mazurfer

http://www.finishlineperformance.com...31-08-1997.pdf

WellThen

Thanks, Mazurfer. I even have one of those Radio Shack filters somewhere around here, Now to find it...

Mazurfer

No guarantees, but worth a shot.

WellThen

Well, the news is mixed. The Ground Loop isolator does seem to kill the noise. However, the sound coming through it seems to be "out of phase", like the polarity of a connection is wrong/switched.

I don't think the isolator is the problem, though. Both the AuxIn connector coming from the Head Unit and the Garmin headphone jack are 4 conductor jacks (on an Ipod, I think the 4th conductor is transport control?). But my adapters to go from 1/8 headphone jack to the RCA connections required by the isolator are 3 conductor (regular headphone jacks). I think that in plugging the 4 conductor plugs into the 3 conductor adapters, the some poles are getting shorted.

So, I guess I need to find some adapters that properly convert 4 pole to 3 pole 1/8" headphone connections. The search continues.

Thanks again for your help!