T610 Portable Handsfree & Ring Volume

Hi,

I've just got a new T610, but I can't seem to find this in the manual.
When I use the Portable Handsfree kit the selected ringtone is sent to
the earpiece and the phone only makes a very quiet beep.
As I use this when I'm in the car, the earpiece is normally next to
the phone, so this means I can't hear the phone ringing.

I've tried setting the ring tone & volume, but haven't had any luck so
far.

Is there any way to modify the Port-Hfree profile to use the phone's
speaker for the ring ?

TIA,

Adam