Comment 6 for bug 637208

Some solution, that solve our problem.
1) xinput --list
It will show you your input devices, our A4Tech mouse have id, for example, there are
⎜ ↳ A4TECH USB Device id=11 [slave pointer (2)]
⎜ ↳ A4TECH USB Device id=10 [slave pointer (2)]
2) xinput set-int-prop %id% "Device Enabled" 8 0
, where %id% is one of id's of your mouse. In my case it was 10. Generally, this is the second id of list. This command will disable advanced built-in keyboard of A4Tech mouse.
If you want to enable back, use
xinput set-int-prop %id% "Device Enabled" 8 1.