Use a long screwdriver and place it oto something that isn't moving, ie not the pulley lol and put the handle to your ear and you should be able to pin point it better.
Lol... Don't say that mate....
Pretty sure it's coming from the aux belt area.
so was i lol
Have you checked for a loose heat sheild?
Also check the exhaust manifold and downpipe.
I am getting a similar issue, I'm sure it is my exhaust that is blowing somewhere in that area.