I just purchased a Esinkin bluetooth receiver from Amazon so that I can use my phone to send audio to my Beosystem 4.

My Beosystem 4  is networked linked with a NL/ML Gateway. 

Within the Beosystem 4 "Line In" is mapped to the NL/ML Gateway audio inputs. I can see this when I go to the Source menu of the Beosystem 4.

I have the BEO 4 remote with the navigation joystick as the center button.

My question is how to I assign a button on the Beo 4 remote to "Line In"?

When in the source list and "Line In" selected the RED button for setup does nothing. I couldn't get any of the color function buttons to do anything. What am I missing?

I have the audio outputs of the bluetooth adapter plugged into the audio inputs on the NL/ML Gateway. Having my android phone paired with the adapter I get music from the phone through the Beosystem 4 to its attached wireless speakers via a Transmitter 1. This works, I just want to be able to assign the "Line In" to a source button on the Beo 4 remote.