One the basis of feedback and some Google signifying it's common for the Nokia units to fail, I opted for the newer unit.

I managed to get a Bluetooth module from a 2010 Range Rover for the same kind of price as a 2nd hand Nokia unit and, installed it in the place of the old Bluetooth module then, just followed the Wiki on here. It took no longer than 15 minutes to fit and set up.

You'll also notice my measures to ensure no connections coming loose!

Click image to enlarge

How's the phone call quality with this? I have one of these newer non-Nokia units but it's very crackly when making calls. Had it out checking for water damage, looks fine. Wondering if a new unit might be worth a shot, sounds like a simple swap from what you've said. 09 RR Westminster 3.6TDV8 - Stornoway Grey / Black interior - now gone (sad face)
Nissan X Trail 1.6TDCi Tekna
Fiat 500 1.2

garyRR i am interested in what you have done but as i dont know what model you have, i dont know if mine is the same or if it will work RR 2005 4.4 petrol
Any spelling mistakes are the fault of spellchecker
Previous MG J2, CITROEN light 15 x 2 gone unfortunately
Present MERC 180e, RANGE ROVER L322, JAGUAR XJS, MERC 280SE, MG F, JAGUAR S-Type 6v 2003, jaguar s-type 8v 2004, Ford Cougar

I can't really comment on the pre-facelift L322.

I think it will only work with a MOST system. You can check this by putting your head unit into diagnostics mode. If there's a 'MOST' test option and you currently have one of the Nokia units then, you should be able to put the newer Bluetooth units in.

putting your head unit into diagnostics mode is a bit beyond me but i do believe i have the MOST system RR 2005 4.4 petrol
Any spelling mistakes are the fault of spellchecker
Previous MG J2, CITROEN light 15 x 2 gone unfortunately
Present MERC 180e, RANGE ROVER L322, JAGUAR XJS, MERC 280SE, MG F, JAGUAR S-Type 6v 2003, jaguar s-type 8v 2004, Ford Cougar

Tugger wrote:

How's the phone call quality with this? I have one of these newer non-Nokia units but it's very crackly when making calls. Had it out checking for water damage, looks fine. Wondering if a new unit might be worth a shot, sounds like a simple swap from what you've said.