Whining defender , update

drove my defender for the first time in months today , and got pi..ed of the whine , (the p38 hs made me soft) , called a mechanic I know and he told me that , on the hicap 2005 they put a "ordinary" rover rear axle , and he also said that whining wasn´t that un common .
comments before I go under the 130 again ??

check the differential grease is at the proper level,and grease your UJ's

Are you sure its not the gearbox?

I have just had my 3rd R380 installed after 36K

The 5th gear layshaft bearings start to collapse and the box gets noisier and noisier, then the synchross start failing.

Wil check the greese and oil and so on ,
Teh rear axel is the only transmission part i haven´t checked changed , new main and transfer box, new front diff , new turbo , with the only result : empty wallet