Problem is known...
I bought a new Mazda 2 the 26th of august 2008 with the F900BT inside.
It worked fine during one week when suddenly I had the same problem as yours.
I came back with the car to the seller, they phoned to Pioneer wich told the problem was known...
I (we) have to wait an upgrade of the Bluetooth program (there is a huge bug in the european version). Sending the unit to repair is useless because when the upgrade of the BT firmware will be available, everything will be fine...
Today, I download the latest update of the F1900BT (official website : http://www.