So I've had my 2013 CC for about a year now, I was randomly watching some reviews from the U.S.A and spotted their version had native voice controls. You could use voice commands to dial phonebook entries and control the sat nav.
The voice prompt was activated via microphone button on steering wheel, which for mine just acted as mute button for audio. They also had an extra action button on the radio, when in telephone mode, showing same icon as on steering wheel.
It appears that VW in the UK disable this for the RNS 315, yet it's active in the same radio unit in the U.S.A.
I've found that I can enable it via VCDS/VAGCOM, it was straight forward as well.
I think this would work for any VAG unit with the RNS 315 unit fitted.
See my video here:
https://www.youtube.com/watch?v=rz0rNarV3oI
RNS 315 - Voice Controls
Moderators: vwnutant, desertstorm, water01