Tanker Bob--As I recall, I had problems within a few weeks when I tried to use first a cheap and then an expensive 32 GB SDHC card. With 16 GB cards, the problems don't start for about six months.
How long have you been using this 32 GB card? The problem isn't that the iPAQ doesn't recognize the card at the beginning. It's that it stops recognizing it after a while.