Just came from an A5. Bought an A3 due to being more practical for my family. Anyway loved the sat Nav system / ami system in the A5 so I have now bought an ami unit and rnse mk2 unit. Rnse until fitted straight in (59 plate) a3 2.0 tdi 170. Question is what cable do I need for the ami unit to rnse unit. Audi don't even know! Please help.