Brightersiderock

whenever i use my XM radio in my car, there is a low humming sound whenever the car is idleing. when i accelerate, the pitch gets higher until i shift. i believe this is called an alternator hum. I have the XM plugged into the aux input on the back of my radio. does anyone have any idea how to fix this, it is really irritating.

Boss_Hotrod

If it is the alt. Check your belt and if it is worn replace it (check the tension). If its good then you need a new alt. Also check the chareback wire as well as other connection to and from the radio. It might just be radio interferance.