Damp footwell

[fsipassat]

Been searching through the forums for any info on why the left hand front footwell is damp on my b6. It seems that it was a common problem on the b5 that was traced to the pollen filter but it was thought that this didnt apply to the b6.
Before i start ripping it apart does anybody know if this problem was solved on this model or any ideas as to where to start?
Thanks folks.