I have the same problem. The manual says there maybe a foreign body blocking blades or bad capacitor.
First, try to open lid of unit and see if there is anything blocking to blades. See if any discharge or vent pipes are blocked.
Second, is to remove unit and take it to have it serviced (i.e. bad capacitor). Not easy to get it out and back in.
I think mine's even worse and there maybe a problem with the motor. Good luck.
ontario_canada
April 2009