So I recently purchased a 2006 Audi A4 2.0t Quattro Sedan and I'm loving the car but my audio is having interesting problems. So my volume control is non existent. I have the stock symphony 2 head unit still in the car. It will turn on and I can even scan through the radio stations but if I try to change the volume using the volume **** or the steering wheel volume wheel I see nothing. I recently started my car and voila, I had audio for my whole dived. The radio station was playing clean and I could adjust the volume, ew, and fader! But the next time I started the car it was back to square one. No sound and volume adjusting did nothing.

I'm fairly certain it's a loose wire in the head unit but would like some opinions. Friend and I found the amp but since the ratio came to the one time and all speakers were functioning great I don't think that the amp is the problem.

(Waiting on the head unit removal keys in the mail now to check)
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Did you figure out the cause? Similar problem with mine.