Before firmware upgrade :
1. Make sure of your AK100’s battery level at least over 80%.
2. Make sure of your AK100’s memory size at least over 50 MB.
3. Don't remove the connection between PC & AK100 while transferring hex data.

[Newly Added function]
1. PRO EQ
   (1) This function will be activated in selecting 'USER EQ' or 'PRO EQ' in the device
   (2) Optimized sound performances can't be worked properly if you change its impedance discretionally.