I've got a ThinkPad T430 laptop with a wireless Logitech K520 keyboard/mouse combo. I'm running Ubuntu 14.04 with XFCE.
The Logitech keyboard works fine when logging into Ubuntu, but then it stops working. If I press CTRL-ALT-F1 (on the laptop keyboard) and switch to console, the keyboard works. It stops working when I switch back to X.
If I run xev, I don't see any input at all from the keyboard.
The keyboard was working just fine on my desktop computer running Xubuntu.
I used to have a wireless Rapoo keyboard/mouse connected to the laptop, and they worked fine. Then I switched to the Logitech keyboard/mouse, and for some reason the keyboard doesn't work in X.
The mouse is working (except for the middle mouse button).
Does anybody have any ideas on how to troubleshoot this?