peugeot 407 2.0 diesel sounds like a hole in exhaust

hi guys, hope you can point me in the right direction before going back to the stealers, My peugeot 407 basically sounds like there is a hole in the exhaust, even when i last had it serviced at peugeot they commented on the sheet that my exhaust had a hole in it but would need further investigation, the other day i was passing by the garage so decided to pop in and get them to look at it, they took a look but said there was nothing wrong with my exhaust, they said to monitor it and see if it got worse, in my opinion its getting louder, so i need to take it back and get it checked, but before i do would like to have an idea of what it could be....... so does anyone have any ideas?

Thanks

Paul

With the engine running, press the palm of your hand against the exhaust tailpipe.....if there is a blow, you'll hear the gases being blown out.
Its a bit premature for an 07 plate car though.
John

Citroen and Peugeot use the same HDI engines but I don't know if they use the same exhausts. On one of our Citroens the pipe got pin holes just in front of the clamp on the rear box. Unfortunately besides needing a new rear box, the centre pipe was needed as well.

Stupidly I misread this post, and thought the car was a 2007 vehicle
My own Berlingo van (56 plate, 26k) exhaust was as rotten as a pear for the MOT last November...including the cat
John