ufischer

I am getting this annoying electrical buzzing noise when I listen to music through my phone (AUX input) and it is plugged in to the power outlets. It increases in pitch and volume when the revs go up and is present when plugged in to outlets in the footwell and center console. I do not get this when listenign to my iPod through the built-in interface.

Anyone else getting this? Any way to filter this noise out?

I am wondering whether it could be my phone (Galaxy Nexus) or the charger/cradle (ProClip)

MICHAELWWW

My daughters phone does it occasionally, but unhooking it and resetting usually solves the issue. She was not charging at the time and am relatively sure it is a Galaxy.

moorejd

Sounds like you have a ground loop issue:
http://www.epanorama.net/documents/g...oop/index.html

Try an isolator, it might fix this issue (cheaply):

Mike in CA

You've already said it doesn't do it with your iPod so I'd strongly suspect your Galaxy device or the charger. For the sake of curiousity, try the Galaxy without the charger and see if the noise is still present if you haven't done that already. The ground loop filter might work; it's a relatively cheap try at a fix as moorejd said.

ufischer

Thanks for the suggestions. Mike, the iPod is connected through its own interface, so I have to assume it is not on the same power circuit as the phone. Therefore the fact that the iPod works fine does not necessarily isolate the problem to the phone. Besides, when the phone is not connected to power the noise disappears. I have tried different charger cables with the same result so it is not the charger.

Having read the write-up in the link provided by moorejd, I think I have the classic symptoms of a ground loop. I have ordered the filter from Amazon and will try it out. I will report back with the result.

I may never figure out the cause of the ground loop but if the noise is gone, that is all I really care about.

Mike in CA

Good point and good luck.

Minok

This is the quite common electromagnetic whine folks have gotten in car audio systems since we had car audio systems. When things are wired or shielded properly on analog connections this can happen.

The aux in put is analog - two analog lines and ground from some device to the input plug, then from there to the preamp in the PCM. Any electromagnetic signal can be picked up by that wire or connectors as if they were antennas. Faults in the grounding could also inject such signals.

What you are hearing is the frequency of the car's alternator and ignition system piggybacked a bit on the audio signal, leaking in from the aux patch cord or in via the power connector.

if its only happening on the power connector being plugged in, then putting in a line-filter on the power to get pure DC should work. If its leaking in via the analog cables, shielding is an issue.

When you use the idock connector, the audio data is likely transmitted as digital information, so the analog pickup noise doesn't affect that digital signal the same way... one of the benefits of digital transmission is that small noise on the signal is irrelevant.

ufischer

It is fixed! The Amazon gizmo worked (see the third post). When connected in-line with the AUX input (in this case my phone) the electrical noise completely disappears.

Thanks all.

RLP1984

I know this is an OLD thread but wanted to just mention that I had the exact same prob with my 09' C2 that I just got, it was driving me insane. Sounded like a Telsa was taking off everytime I hit the accelerator. I read this then just now when I was going uphill and hearing the sound pulled my Bluetooth receiver out of the AUX and USB and, sound stopped right away. Hopefully that closes the issue out, also ordered the same gound loop isolator off amazon.