I had this exact same problem. You have probably tried this...I found with my machine that the white seal on the front clear lid had alot to do with it. After I cleaned out that seal and put the lid on again I regained alot of suction. I think junk gets stuck on and under the seal and even though the clear lid fits on it, it must not fit tight enough. I had cleaned it once before and told my husband I seemed to have made it worse. It would hardly pick up at all. He did the process all over again and now it works like new again. By the way, you are right,the suction on these things is out of this world. I bought a new dirt devil vision turbo that will suck up stuff 4 inches away :) I have 2 puppies and 3 kids, This greatly cut down on the dog hair and dirt I was having to clean out when I was done.
Jamie, June 2006