Intro: 2001 Audi A4 Bluetooth Adapter Installation
I added a Bluetooth adapter to my 2001 Audi A4's Symphony radio, and it sounds great! It cost me $12 on ebay with free shipping. The adapter supports Bluetooth 2.0. I previously added an iPod/Aux adapter to this stereo, which this adapter is then plugged into. You can also just buy an aux/blutooth adapter which connects directly to a Symphony radio.