Before firmware upgrade :
1. Make sure of your AK120’s battery level at least over 80%.
2. Make sure of your AK120’s memory size at least over 50 MB.
3. Don't remove the connection between PC & AK120 while transferring hex data.

[Newly added function]
1 . Support DSF file tag

[Bug fix]
1. Correction of not changed music information & album art in case of changing music automatically under deactivation of gapless.