Stragne Bluetooth Phone issue - Help!

I have a strange Bluetooth phone issue that I can't figure out. I am hoping the collective experience of this board may be able to help. Here we go...

I have a very new Prius with option package 5. I have no issues using the Bluetooth hands-free phone option with several people on land lines (I have not talked to anyone on a cell yet). A colleague at work that I talk to frequently using in my car has an ear piece and a blackberry that he has used to talk to me for over a year without an issue (I used my Blackberry and an ear piece in my car prior to my Prius without issue). Now for some reason whenever I talk to him, and only him, as I start to speak the static on his side increase to the point that he can hear me. On my side it should like a semi-truck is pulling up outside his car. Once I stop talking the static dissapears. The result is that he can't hear me. The only variable that has changed in our connection is the Bluetooth in my car. We both are using the exact same phones and he is using the exact same ear piece.

It is almost as if I am getting some type of feedback loop in my car that builds to the point of overwhelming the mic in my car.

Any thoughts?

Thanks,

Tom

 

FYI

I use a Blackberry 8700c and my carrier is Cingular.

Thanks,

Tom