I havn't got many responses, so heres some more info.
the car has 120,000 miles with FSH every 10,000 miles and I have a print out of all the parts purchased in the last 5-6 years one of which was a new cat, I've got a feeling that something could be restricting the exhaust causing excess pressure in the two pipes, anyone have any ideas, is the cat in front of the flexi pipe with a sheild on it? If so then i belive that is what is rattling, Never had a car with a cat before!
