Our 2007 13' dinette/bed cushions have developed a moldy smell. The covers were replaced ~ five years ago, the age of the foam is unknown. Although there is no evidence of water contact, we find condensation on the table top in the morning. In other words, vapor is passing through from us to the table top below. We plan to clean the covers, but would appreciate information on how to do that - dry clean, tumble washing machine? Should we put down a vapor barrier sheet before making up the bed? Any advice will be welcome.