I've contacted AVIN with no solid answer support from them.

We have an E61 that has factory aux installed. Plugging a phone into it plays music normally as expected.
spec'd out the AVIN unit on their site and went ahead and installed it. Install went smooth, I moved the optical cable per the videos I've seen and when the Android unit is playing audio we only receive audio from the right front of the car. Now, AVIN claims my car has a fauly AUX port/cable causing this but I do not see how this is possible because every aux junction on the car has been tested with a phone and audio is sent to all speakers.

What gives? Wife is annoyed - and so I am. I spent $500 on a device that arguably performs worse than the OEM stuff...

 

I really don't know that I would have messed with the stock system on the E61. I have little bluetooth USB adapter plugged into a usb power plug right next to the aux in and a short aux in cable from it to the aux-in port and it rocks the vehicle when I turn it up. I have a Dyanvin N6 (similar to the Avin product) in my E46 and it is much better than the stock Nav unit I had but it's nothing compared to my E61.

-r

 

I bought my unit from Aliexpress. It had f'ed up wiring. It is very common. Also it is possible to damage the wiring if your car has navi as it comes with 5 miles of cables that are not needed. I ended up removing 75% wires as they would not fit without damaging the car. It was a big ass project to finish. Also the audio quality of this devices is short of nightmare. Complete garbage. $20 phone from walmart will run circles around it. I had to modify my unit by replacing resistors and caps to gain the bass back. Though it will struggle with Aux input with awful input impedance.