Although I don't have a Cayenne, this should still be a relevant question as the interfaces may be similar with my Carrera.

I have a Universal Audio Interface.

My iPod works just fine with it, but the quality is poor due to the fact that it is not a 5.5G (uses Cirrus DAC). I am considering purchasing a Zune, for superior sound quality (Wolfson DAC).

My question: Has anyone used a Zune with this version of the PCM, and how does your degree of control over the Zune compare to the iPod (which is excellent).