the carpet has a musty sour smell, dirty sock smell, definately not sewer, or chemical oders. Just smells old. I've scratched my head to the point i can only point to one thing, we just moved to Houston in the 5'er and with constant high humidity, and cool days/nights, we don't run the AC nor the furnace much. so the humidity inside is as high as it is outside. didn't have this proplem throughout the summer, AC was condensing inside air and lowering the humidity. Nonetheless, carpet stinks mostly were foot traffic is.
So......I'm considering ripping up the carpet in the living area first (about 5'x5' section) (not including the slide area) and go back down with either self-adhesive or glue down type carpet squares with no padding. If that goes well, i'll venture onto the slide. The slide poses a problem I haven't figured out yet because it carries the two recliners and dinette. I'm interested to see what can be done about the trasition piece. It needs a decorative, but functional hangover skirt to hide that joint. That carpet flap-piece that hangs over the joint is sewn on the ends of the carpet and it would be deficult if not impossible to recreate.