Hey folks, this problem just got fixed for me.   Setup: Fiio X5 Gen 2 with FW 1.1 (the one it was shipped with) + Macbook Pro Retina (2015).   Fix: Updated FW to 2.1 (procedure - http://fiio.me/forum.php?mod=viewthread&tid=39948&extra=)   Now my mac recognises both as storage and as a USB DAC