Ok, quick update.
Picked up my Kenwood BT50U yesterday & had a quick attempt tonight at getting it going.
As you only get a manual on a CD (didn't have time to take the laptop out to the car) i thought i'd give it a quick go by just randomly blundering through the settings...
Both devices can "see" each other, the HU shows the phones name on the display & the HU is in the devices list on the Desire. Great.
But then i have a problem, not great. Everytime i long press and click "connect" on the Desire it scans for a few seconds then i get the "headset disconnected" message on screen? and the connection fails. If i try connecting the BT via the HU by selecting the phones name is attempts to find the phone (i have made it findable in settings) but it doesn't manage to connect that way either.
I've also tried firing up the music app and sharing a track via BT which the phone says it sends to the HU but nothing happens. The phone will play a track but without any volume as if it thinks the HU is playing it over the speakers.
Also the other thing that the HU is doing is showing "downloading" on the screen whilst it attempts to sync the phones contacts to the HU but it just doesn't seem to complete the sync.
After a bit of searching through posts on here i found another member who is using a Kenwood BT60U that seems to be working (streaming & phone use via BT) and also having the problem with not being able to get the contacts on the HU.
Hopefully it's just down to a setting that needs enabling or im doing something wrong on the HU as overall it's a pretty nice unit with plenty of options. I've tried both the usual passcodes (0000 & 1234) but neither seem to allow connection.
Any ideas would be helpful, it seems the Desire isn't the greatest when it comes to bluetooth....