Stinky Diaper Champ?

We have used the Baby Trend Diaper Champ for 5 months now and it is absolutely rancid. We empty it often, and have even tried bleaching the inside hoping to get rid of the smell. We have started wrapping the poopy diapers in scented bags before disposing of them in the Diaper Champ, which we shouldn't have to do according to the company's claims. This still hasn't helped. Any ideas, has anyone else had this problem with this product? Does anyone know if Diaper Genie gets stinky too? My daughter's room wreaks right now and the Champ is empty. Not so much of a "champ" if you ask me!!!