I try several things to make work the GUI ofRetroarch on my smartbox X96.
I try a lot of diferent devices, joystick, gamepad, keyboard, mouse, and the original control remote of the box x96.
In any case I get the mensage “DEVICE” is not configured…
All my devices work on the box I can use them in the browser, any other app, or emulator.
There is something that i can do? something toedit in the config file?
PLEASE HELP
EDIT FOR P/D: Running android 6.1 on the x96.
Same thing for me, input is not working but I have connected both keyboard & mouse.
I’m testing the last build from the GIT repo of FDROID, dated 01/03/2017.
Androidx86-6.1-rc
X96 is a chinese android box, is not de x86 plataform. I have a computer where I installed the Androidx86-6.1-rc, i had the same problem as you there, but i was able to fix it using a older version of retroarch, go to http://buildbot.libretro.com/stable/ start to instala from 1.2.0 you will find one that work.
Still the problem remains, looks like there is a big bug with android 6.1 and the input driver, hope the staff put some light and help on this.
Yeah I know, but that’s not a solution at all 
The thing is to test the latest build so developers can debug and solve errors faster. There’s no point in downgrade your version if you want to see the improvements…