Transmission whine

[DKL]

I've had my car for nearly 12 years now and all this time there has been an annoying whine from the drivetrain. I get this when under load so when accelerating and changing down. I can get rid of it by feathering/easing off the power on a flat road but as soon as you get on the power it returns.
The awkward thing is that it seems it has been there from new as the man from autocar moaned about it. See here

http://www.autocar.co.uk/CarReviews/RoadTestsLivin...

This my car.
Anyway enough is enough and it would be a far more civilised drive wihtout it. So where do I look?
It sounds a bit diff like but he seemed to think propshaft or gearbox (I hope not - its a 6 spd)

So thoughts?

[Smollet]

Do you have an LSD?

[mickrick]

TADTS!

[ArosaMike]

Indeed they do all do that. It's the diff that causes the issue and the tolerancing is all over the shop. There is a guy that Caterham Midlands can direct you to who will rebuild them for about £200 if you want to get rid of it the whine!

[DKL]

No LSD.
I hope they're not all as bad as mine it's annoyed me for ages.
Any decent transmission cos in wiltshire?

[Nicodema]

The generally accepted experts are Road & Race Tranmissions in Shoreham.