It is possible to use a 128Mb MMC with the MM-FX500, but the card has to be formatted on a PC. I did it using the fdisk command on GNU/Linux. The Aiwa expects the card filesystem type to be FAT16<32Mb, so using a usb flash card reader I changed the partition on the card to type 04 and then reformatted it as FAT16. About 125Mb is then available to the Aiwa.
Paul Howard
February 2006
The most this unit will handle is 2x64meg cards. This would give you 128meg of storage. A card larger tahn 64meg won't work.
Harry
February 2005
I can answer this question...
Aiwa FX500 MP3 Player only uses 20MB of a 256MB MultiMedia Card, why?