zte 246 (Vodafone 246) DIY Headphone?

I have the above mentioned mobile phone.
I want to use it as FM Radio reciever only.
But for the Radio to function, I must connect Headphones.
So I have to make an 'adapter' between the 3.5mm Jack of my headphones and the USB Micro-B of the phone. (headphones can be attached to USB only).
USB Micro-B has 5 pins.

USB 1.x/2.0 Mini/Micro pinout
Pin........Name........Cable color........Description
1..........VBUS.........Red.................+5 V
2..........D−............White...............Data −
3..........D+............Green...............Data +
4..........ID.............N/A........Permits distinction of a host connection from device connection:
...........? host: connected to the signal ground
...........? device: not connected
5..........GND..........Black................Signa l ground

pin 2 will be connected to the one channel of the 3.5mm jack.?
pin 3 will be connected to the other channel of the 3.5mm jack.?
pin 5 will be connected to the GND (common) of the 3.5mm jack.?
pin 4 not connected?