I have now sold my GTI and have this usb sdcard mp3 player with aux in for sale.
VW USB Adapter. Also Includes Inputs For Aux & SD Card.
Features & Benefits
Plug and play, no cutting of wires required
Plugs into the original CD changer port on the rear of the car stereo (Not for FM based products), therefore offering high quality audio
Control track up/down and folder up/down from the stereo or steering wheel controls
Provides USB power to the device connected.
See
https://connects2.com/Product/ProductItem/CTAVGUSB009for compatibility list.
£30 posted.