[ricethief]

Sorry to drag up an old post. Just posting this in case anyone else has this issue and can’t find a fix. Aux/Bluetooth/USB/SOS were not working on my 2011 328xi BMW Professional radio for the last year and was killing/annoying me.

All the MOST loop connections were connected and no burnt fuses. I checked the MOST loop at the connections by the ODB and in trunk but, it was completely dead everywhere. Pulled the head unit out and pressed the clips to pull the MOST cables off the head unit harness. Plugged the harness into the head unit and used a mirror to see if any light was coming out of the MOST port on the back of it when powered on. There was no optic light coming out of the head unit MOST port. Bought a used head unit off ebay with the same exact part# and installed it. At first AUX/USB didn’t show up but, after being on a few minutes everything started working like it should and was able to pair my iPhone. $75 used head unit on eBay fixed the no AUX/Bluetooth/USB problem I had. Everything other than Aux/Bluetooth/USB was working fine on the old head unit so I didn’t suspect it was the head unit.