Im having problems with my new 64GB card in my Sansa Clip. i can load about 5GB worth of music on it and it starts to fail. Files dont copy over properly at all. The Clip itself is fine - and I work on mac - done all the reformatting do daa but still it persists. I may be wrong but does anyone know if its due to it being a standard Micro SDHC card. Should I have got a Micro SDXC?
All 64GB cards are natively SDXC and are formatted as exFAT. This format is not supported by any current mp3 player, SanDisk or otherwise. There is no such thing as a 64GB SDHC card.
People have had success in re-formatting these cards to FAT32 in order to be able to use them in their players, however the SanDisk firmware has a database limitation which you may be hitting. Some more (detailed) information from you might help someone here figure out what’s going on.