Bluetooth hands free sound quality?

[jlavery]

I've got a Parrot CK3100 bluetooth set which gives good call quality with my daughter's Sony phone.

However, with my Desire, the results are very variable - usually the other party complains of excessive background noise (even when the car's stationary). Usually I can hear them absolutely fine.

I've just reflashed the CK3100 to the latest firmware, with no improvement.

Anyone else having this problem with their Desire?

Thanks,

James