Does anyone use hands free *and* streaming over bluetooth for their car stereo head unit? I have a Sony MEX BT2900 and while the audio streaming is good, the hands free voice is awful! The people I call say that their voices are echoed back to them. After some searching, I found other people have the same problems. This leaves me with no alternative but to find another unit. I'm thinking of the parrot RKi8400. What are your experiences with bluetooth head units?