2005 Jaguar X-Type clutch stripping

i have a 2005 xtype 20d, the clutch has stripped the friction surfaces completely off. it did the same 12,000 miles ago, there is no fluid contamination, but the flywheel and clutch have got very hot, the flywheel, clutch and slave cylinder were replaced last time( which had failed in the same way). I cant find any reason for this failure, can anyone help?

Thanks James