XS3868 BT Headset

I’d like to build a Bluetooth headset adapter using the xs3868 chip. So far so good, i can listen to music but I am not able to use my headset microphone to speak while I’m giving a call. Could anyone send me a sheet, how to wire a headphone jack to the xs3868? Especially the microphone wiring. Actually I am using apple headphones connected by a four pole socket.

Cheers for your help.