I've got the same problem, I havent come up with a tested solution yet but I'm pretty sure if you take the belt housing off the back of the machine (2 x phillips screws) you will find a silicone belt for the fan that will have come off the pulley. Put it back on and more than likely you'll have it sorted.
I made the mistake of taking the entire back of the machine off and now have to try to work out a way to get the drive belt for the barrel back on. Bit fiddly.
Hope that helps, or that you've got it sorted in the meantime.
Luke Neesham
July 2008