I'm having the same problem. Mine started making a loud noise the other day when I was using the attachment to vacuum off some cushions. I have cleaned all the filters & hoses, I checked the belt. I just can't figure out whats wrong with it. Maybe someone will come along that can give some help to us. My vacuum is a Dirt Devil bagless Hepa filter. It's very loud now when I vacuum. Plus I don't think it's suction is as good as it was before, but it still picks up.
Molly, October 2009