If your radio is the RCD 300 you can fit an aux adapter.
There are two types of aux adapters:
Analog adapters - those are basically just a cable with a 3,5mm plug or a socket. Some of the socket versions can be fitted into your dashboard.
mp3 adapters - these adapters are designed to replace your original CD changer and use an usb stick or an SD card to play mp3 files. The adapter acts like a CD changer, you can control it directly from the radio.
You can get both types from eBay or other stores. The analog type is probably cheaper.
Just google for "RCD 300 aux".
Both versions require your radio to be removed for installation, AS the cable needs to be plugged into the back of the radio. However, this is a simple procedure and there are tutorials available how to do it.
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