Well after many months of trying and heart ache Mazda finally sorted the rattle.
To be honest they did not have a clue, they took my car in first week of June 2015 and I got it back 1 week ago, they did test after test (well as much as a computer would test it) they sent the results throught o Mazda UK then to Mazda europe, the eventually a guy came over to Guernsey to take a listen and he was sending the results to Mazda Japan.
To this day they still do not know what the rattle was so the stuck in a new engine and sent the old one off to be examined, they think it was the little ends on no 1 cyclinder.
so 1 1/2 weeks before my holidays (road trip round europe) I gets the car back to try and run in, got nearly 400 miles on it at this time and the rest will be done on the motorway, I am old school and beleive metal on metal need to be bed in no matter what the toloerences.
It was getting very heated in the conversations near the end as you can appreciate an engine with 660 miles on it is still in the car after 7 weeks of testing and then they decide a new engine is needed. I was not a happy bunny near the end but Mazda refused to put in a new engine or strip the one I had to find the fault, all because the computer could not tell them anything, technology is great but you cannot beat good old fashoined mechanics, hear a noise strip it to find the fault.
Ah well the new engine feels better and more free running then the origional, its as though the electrics knew there was a problem and would only let it run to what it thought was safe, as it seemed tight and restricted, so the trip of 3500 miles will let me know if the new one is ok.
getting better miles to the gallon too, whilst driving around I am averaging 45mpg and thats in Guernsey