Comment 7 for bug 1069053

Same here. The machine frequently loses the custom keyboard shortcuts which I configure in Settings/Keyboard. Some examples include closing windows with Alt+W, switching to workspaces by Win+1, Win+2, etc.

If this helps, I use a Thinkpad x220 docked to an external monitor and a keyboard. Initially I thought this happens when I dock/undock it, but even if I leave it docked permanently it eventually resets to the default behavior.