SD card formatting

If it works exFat is preferred for large drives and copying files is much faster than the universal FAT32. Size rarely matters. (Not what she said.)
exFat works in my A&K, NOT in  my Cowons.

Thank you.  I appreciate your explanations regarding my question.  I'm having some difficulty regarding another matter, and perhaps someone can resolve this.  I don't wish to keep imposing myself upon forum members, but I've contacted both Hiby and Microsoft, and their collective solutions aren't working.  My PC runs on OS 10, and Widows Media Player (WMP) refuses to recognize my DAP.  Hiby recommends dragging my music files from my computer (HD?) onto the "inserted Micro SD card."  I'm guessing that means the R3 Pro icon.  I've tried, but it doesn't work.  Let me add, all my music files were inexplicably uploaded to my OneDrive account, and WMP's Music library displays only "OneDrive and Music," and there's really no alternative options to add.  If I remove OneDrive from the WMP library, all song titles disappear, then, of course, reappear when re-added to the library.  My point being is I'm unsure how to access music files/? on my HD.  Yes, I'm something of a terminal neophyte regarding computers.  Microsoft's solution was to reinstall the 10 OS, but WMP remains the same.  Perhaps the dap is malfunctioning.  Thank you for time.            

When the SD card is formatted, all data will be deleted. So the best option is to recover deleted files if there are any. How to do it? Then read this; [4 Easy Steps] How to Recover Formatted SD Card on Mac – SD Card Recovery

How are you trying to copy your music files to the SD card? Is it installed in the Hiby? If so remove it and put it in an SD card reader to copy the files before inserting in the Hiby.