BC127 in Incoming Call uses Phone Microphone

I’m using two digital microphones connected to ADAU developer board, and this board is connected to the BC127 Discovery Board.
When I make a call the microphone used is the two digital ones connected to the ADAU board, but when I receive a call even though I’m still connected to BC127 the phones’ microphones are the ones used in the call.

Is there a way to control this so I always use the ones connected to ADAU?