sansa clip and SDXC 64 GB (speed 48 MB/s)

maybe this answers for somebody question

Sandisk Sansa Clip+ - 8GB
Rockbox
Sandisk SDXC - Ultra (Dark Grey) - 48MB/s - 64GB
guiformat (Windows GUI version of fat32format)
(from "box" dont work, but needed format)

and works  perfectly