First, please read this post fore more: How to Update Firmware on Amlogic TV Box, Rockchip TV Box, Allwinner TV Box
Also, you can ready this post at TV Box Forum: How to flash a Firmware (step by step)
The following video is from NEXBOX team:
Also, somebody also made a video as below for reference: https://www.youtube.com/watch?v=psCVNj9In34
Firmware for NEXBOX A95X(S905X) system update. Anyone who needs new firmware please follow the right link and download the file, tools and instructions are included.
1.Newest firmware for NEXBOX A95X S905X (1G+8G)
Newest firmware for NEXBOX A95X S905X (2G+8G)
Newest firmware for NEXBOX A95X S905X (2G+16G)
2. Installation Guide(ONLY FOR REFERENCE)
Default installation, keep click “Next Stop” , do not change the installation path
Open install path, click “InstallDriver.exe”
Open the tool and Import files “XXX.img”
Check options and click “start”
Connect the box with computer, then plug it in. If the connection failed, pull out the USB cable in the box and unplug the box. Try more times.