First of all a massive thanks to Audi Retrofit as they inspired this little project and it was there instructions that I used to get this working.
The only problem with their solution is that it cost well over £100 to complete as it used all original Audi parts. This made it too expensive for me given that it's just a little gimmick and really not required, That said it does put a little smile on my face every time I use it. My solution requires nothing more that a switch which cost £17.20 and a small length of speaker cable. It took about 2 hours to complete and was fairly easy. The button I used fits perfectly in the original cigarette lighter hole although I had to slightly adapt the buttons retaining nut to get to fit in the housing. I have also moved the lighter in the space next to the Aux socket.
For a step by step guide;
The switch I used;
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