Hi All,

I've got a 53 plate A3 FSI Sport and when using my card reader (plugged in through cd changer port) I get a constant humming sound on the rear speakers, I understand this can be solved with a ground loop isolator. Where do I need to attach this? I heard that there is a small amp in the back? Or does it need to go on the rear of the head unit?

Any help much appreciated.

Kind Regards, Harmeet