MX3 Air Mouse back button not working

[kostaman]

Have a read of the below post as it may or may not be your issue

[solved] Key code 0x00 always switches to mouse mode

The problem is you disabled fn_key_scancode in your remote.config. So the function key is 0x00 to switch remote mode and when you push Back on your remote the controller receive 0x00 and switch the mode. So find any free number like maybe 0x12 and change this in your remote.config: before: #fn_key_scancode = 0x4c after edit: fn_key_scancode = 0x12 Then it should work with this button (0x00) as fn_key_scancode is not anymore 0x00.