When my wife uses the dryer a foul odour comes form the unit as soon as the spin cycle comes on. It is only when the dryer is on the FIRST time and the spin comes on to flush out the water. I have checked the drain in the basement and there is water in it.
Answer:
There could well be something stuck in the catch tray if you have one. These things don't have drain hoses so you can be sure there is something stuck in there somewhere.