Hello, Audittmusic.
Welome to Apple Support Communities.
It's my understanding that you want to stream music from your iPhone to the Audi TT 2009 speakers. I can help but this would mainly depend on the system of the Audi TT 2009 if it can support it. There are usually two ways to stream music, one using a connected cable or Bluetooth media streaming. Apple has a great guide that can help with this: If your iPhone, iPad, or iPod doesn't connect to or work in your car
Let us know if you have any questions on this.
Cheers!