You might want to give OdoBan a try.http://www.cleancontrol.com/OdoBanRe...dorOdoBan.html
It is available at most Sam's Clubs. It is a deodorizer, sanitizer, virucide, disinfectant, and most imporatantly for you, a mildewstat
I used it to remove the remaining stench from my refrigerator after Hurricane Rita. Imagine a fully stocked refrigerator left closed without electricity for ~ 3 weeks during the summer.
It eliminated all residual odors from the fridge after I thought that I had already thoroughly cleaned it.