Murketts, are they still THE place to take a CSL ander warranty ?

[XPorker]

Hi all, I'm struggling to get a problem sorted out with the car.
It's has a rattle/clacking noise from the rear end.
Whilst I was up at Simpsons M/Sport having other work carried out, they found a broken rear spring. The pair of them were subsequently replaced under warranty. (as were the rear damper top mounts too)

The "clack" only appears when the car is hot. It can be felt through the floorpan at the leading edge of the boot and directly behind the N/S section of the rear seat when it's been dropped down.
It looks to be in the area of one of the subframe mounts.
The car has been in three times now and still the problem hasn't been rectified.

Whilst I was at Simpsons it was recommended I try and claim for a diff (not to cure the "clack" but as a precaution against incurring a big expense in the future and whilst my car is still under warranty !) as they seem to wear and then get noisy.

On my latest visit to my local dealer yesterday they've said they're going to replace the diff in an attempt to rectify the "clack"

I'm pretty sure it won't fix it, but hey, a new diff is a new diff !

If this doesn't rectify the issue I'm thinking of taking the car down to Murketts who though I've not used them before ( in the past seemed to have a good reputation (and been very knowlegeable) whilst beeing happy to process owners warranty claims for the "usual" CSL issues)

It'll be a nuisance (I'm in Birmingham) but my patience is wearing thin with my local dealer and their inability to fix the car.

Firstly has anyone else had this "clacking" issue ? and secondly any comments about Murketts, their service (and if positive) a contact name ?

Many thanks in advance. XP