Hi Ady....welcome to the Forum
Great idea from Dan3222 (aka. cheapskate) but also the suggestion that Steve Q has offered is equally valid.....your choice
I like the idea of the after-market system as it offers a lot more beside, such as SatNav, telephone, phone mirroring, media, etc
Have a look at the ones here: http://www.iceboxauto.com/audi
Let us know how it all goes
Cheers, Trevor