I installed the Parrot 3100 Bluetooth device this weekend. Works relatively seamlessly with the stock TT PCM. When you make or answer a call the PCM is muted and reads "external phone active" on the PCM screen. Very happy with this sub $200 investment. I used info from BeckerAutosound.com, Parrot.biz forums, Rennlist forums to gather wiring and PCM removal info.