Bug 264196 seems to be describing the same issue, but over there they've found a few workarounds! Here's the one that worked for me with the least nasty side-effects:
Add this to the end of xorg.conf:
Section "ServerFlags" Option "AutoAddDevices" "off" EndSection
The downside is that any extra keys on your keyboard (such as "multimedia keys") won't work.
Bug 264196 seems to be describing the same issue, but over there they've found a few workarounds! Here's the one that worked for me with the least nasty side-effects:
Add this to the end of xorg.conf:
Section "ServerFlags"
Option "AutoAddDevices" "off"
EndSection
The downside is that any extra keys on your keyboard (such as "multimedia keys") won't work.