Thanks both.
After I posted I took it back to the place where I had the map etc. done. They plugged in the VAG com and there were no fault codes. He then read and wrote a new map with some tweeks but it still does it.
I will probably look to see if I can get it back to its original state with the DPF mapped out as you suggested Rhyso

Also, itavaltalainen - thanks for the offer
It seems like its going to be one of those annoying problems, that could be something so small and annoying but could cost a few ££ to find and fix! 95% of the people would say its fine, but I'm one of those people that won't rest until its fixed!
