If you have a case that smells musty, if you use the x strength Febreeze and put it in the sunshine, most of it will come out. You may need to do it several times and, store it with the lid open, until most of the smell is gone. I bought one on ebay and the smell was really bad and that seem to work really well. It usually isn't from moisture. The machine is in excellent shape, it was just the case. I use it all the time, in fact looks like a brand new machine. The Featherweights have a oil felt in the bottom of the machine. If it hasn't been cleaned or changed, that is where most of the smell comes from and it transfers to the cloth or paper that lines the cases.