There have been a lot of threads on here about noisy diffs recently. It's always a tricky one ad there are several confounding factors:
The car's design means the diff noise is far more noticeable than in a tin-top
Some 7s have tunnel covers, upholstered seats etc some do not and this will affect the noise heard
Some of us drive with windscreens, some with aeros
Some of us drive with hearing protection, some don't
The diff noise sounds different from driver and passenger seats
Some have exhaust exits on the right some on the left (exhaust/induction noise may mask diff noise)
Some of us have engines that give max torque at 3500, some at 12,000 rpm
Some of us have rubber in the drivetrain some don't, some have rubber in the engine/gearbox mountings, some don't
Many of us run wildly different gear ratios and diff ratios, even different ggearboxes, some with short propshafts, some with long 2-piece affairs with intermediate uj
Some have lightened flywheels
And so on... all of these things and more will affect diff noise
My point is there are many many reasons why it's very difficult for one owner to comment conclusively on another's diff noise. More often than not the cause of the noise you hear from the diff is elsewhere, even if it actually does make the diff louder.
So, to put the complaints about noise in perspective, how many people have suffered a diff FAILURE, how did it fail and did it make a specific or louder noise before doing so?