Of course you can use official way to update the firmware.
But also here the programm which allow to update firmware without internet connection.
Home Page: http://deus.lipkop.club/ (no longer supported)
Direct link to download
This software IS NOT OFFICIAL updater and is intended for use solely for informational purposes.
The author is not responsible for any damage (material, moral or other) caused to you or third parties resulting from the use of this software.All the steps you are at your own risk!
How to Use
- Run the file dou.exe and wait for the update (internet connection must be available).
- Turn off all you headphones.
- Turn on the remote control WITHOUT the USB cable.
- Go to update mode (Option > Configuration > Update > Confirm).
- Connect the single USB cable between your PC and the remote control (don`t use the recharge cable with 3 mini USB).
- Follow the further prompts of the program.