Before firmware upgrade :
(1) Make sure of your AK100’s battery level at least over 50%.
(2) Make sure of your AK100’s memory size at least over 50 MB.
(3) Don't remove the connection between PC & AK100 during transferring hex data.

[Improvements]
1. Support AIFF , ALAC , AAC codec (Updated tutorial contents about APPLE codec)
2. Moving out to upper list menu by long pressing back touch button (←) after approaching to “setting” menu