iPod Touch (2nd Gen) Bluetooth Streaming Audio to Aftermarket Car Stereo???

I've searched and searched online to find an article where someone has successfully paired a 2nd Gen iPod Touch to an aftermarket car stereo and streamed music through bluetooth. I've been to Best Buy a couple times and looked at the Sony MEX-BT2700 with built-in bluetooth. I can get them to pair up, but no audio comes through even when I select the output on the touch to go to the stereo. Has anyone successfully streaming bluetooth music from their iPod Touch to a aftermarket car stereo with bluetooth?? I don't like wires and would love not having any. Thanks!!