On this particular model there is a plastic guide situated on the underside of the shredding wheels, this can become dislodged and be inadvertently thrown away with the shredded waste.
If this has been lost then the paper can get caught against the moulded plastic lid, the best way to keep things working is to avoid the shredder bin filling up. It maybe worthwhile contacting Fellowes to see if they can supply a replacement part.
Bill, April 2005