For whatever reason the Mac puts a Spotlight folder on the SD card. Your files are probably saved in that Spotlight folder. Transfer them from the Spotlight folder to the MPLANG folder on the Marantaz itself and then you will be able to read them. After you finish transferring your files. Wipe the entire card clean and re-format it. Then before you plug it back into your computer, record a short file that you can keep in the MPLANG folder (I named mine DONOTDELETE) at all times. This will insure that all future recordings go straight to the MPLANG folder after the Mac creates another Spotlight folder. Hope that helps.