Hi Tim
Quote
"Data Storage Card drive for Secure Digital (SD) and MultiMedia Card (MMC) Memory Devices"

I'm guessing that could be your problem, it mentions SD but not SDHC. Do you still have an old MMC card from a Yammie?

Even if you can only use 2gig sd cards, they'll go an awful long way. Only reason you'd need anything larger would be for sample data which of course the PA500 doesn't load samples anyway.