It's a bluetooth protocol that allows two devices to share streamed stereo/mono music media ie. no wires needed to get music from phone to car audio system.

Stocky
I really do not know about AD2P etc, I just know from 2009 on they used a totally different module from a different manufacturer with a different connector, that has a lower price (New), and those that have retro fitted that module on D3's at least, are well impressed with the improved pairing compatibility and audio quality improvements. Seems like the newer unit is indistiguishable for a Land line while the older is more head in bucket. The item is fitted across the board on all 2010 on as well as all Freelander 2's

nbunney,
It's an LR part and would come with its latest software pre programmed in, but as mentioned although it can be directly plugged into the MOST bus in place of the old, it's main connector is different, so its not just a plug and play replacement item for anyone having the old one already fitted.
What you have to appreciate is that there are 3 connectivity elements to the Phone module,
1) Power and ground supply
2) Connectivity to the cubby box cradle. That cradle also has a coaxial connection to the FIN antennea.
3) MOST fibre optic infotainment system.

For me and any retro fitter, i recognise that the cubby box cradle connector and FIN connection is about as much use as a concrete kite.
So using a 2 pin header to supply just power and ground to the module from wires perhaps tapped into of the old connector etc, and plugging it into the MOST gives us total Blue tooth functionality and connectivity.

bigl322.
The reverse cam has a direct coaxial feed direct to the back of the TSD. It has to be enabled in the CCF but if fitted from factory i doubt thats your problem. There is a five amp fuse, number 8 in the RHS luggage compartment fuse box for it which might have gone  2003 4.4 HSE

hi just checked fuse no 8 and its the rear heated window ?? any other ideas were it could be thanks

Do you have power at the CAM end? 2003 4.4 HSE

just been looking at this camera again as its bugging me again
i checked and there is power going into the camera but nothing happening when reverse is selected

google>wikipedia
http://en.wikipedia.org/wiki/A2DP#Advanced....28A2DP.29 
RRC 2Dr, RRC 4Dr,
P38, and 2 L322s
(wife thinks I'm nuts - prob right, too)