Tore out all the old carpet padding today. Does that stuff ever stink after 32 years. It smells like an old basement. I need to find something modern to use that does not absorb moisture. Any ideas?

"AirEx" brand closed cell foam? (USCG approved material for making boat seat cushions which double as floatation devices) Available in many different thickness starting at 1/4".

I haven't used it, but it was suggested by my local foam materials warehouse.

I used the the thermal/acoustic insulation that MSA sells. Very easy to work with.