spts

Hey all. Second tech question for me here so I hope someone out there can help.

I've got this strange buzzing noise coming from the stereo and it seems to change tone when the engine revs (higher pitch). It happens now and then, but now it seems to be more frequent even when the music is muted. Could this be a grounding issue?

CalvinC4S

Do you have aftermarket plug wires on the motor?

spts

Nope, the wires are OEM.

Kika

Do you have an external amplifier? sounds like alternator whine, a ground loop isolation should help between the head unit and the amplifier.
odd if it just started, did something change on the stereo system?

could also be a noisy power supply to the Head unit and alternator is creeping into it and being amplified.
a good stereo shop can put a filter on the power line (large farad capacitor basically) or run a new clean power line.

vincer77

I have a CDR 220 with an iPod adapter and hear the noise while playing the iPod. I do not hear it on radio, but it may be screened by the added noise of FM. I do have a external amp also.

Stealth 993

Pull it out & clean up the contacts, that humm is a ground loop, it's a poor ground, or a ton of noise. If cleaning & reconnecting doesn't work, you can get a "ground loop isolator" it goes in-line with the decks power & should work.

TheOtherEric

Did you have the World Cup on a TV in your garage by any chance?

Kika

I had exactly the same issue, get a ground loop isolator and put it inline between the iPod and the headunit.