I am using a X220, and decided to switch to Xubuntu. Everything works perfectly well until I try using the laptop on a docking station with an external display (I want to use only the ext. display when on dock). On Xubuntu (and also Ubuntu and Lubuntu as well) windows sometimes act 'transparent' to the mouse cursor - when I click or drag and drop, the action either affects only the desktop, or the window that's behind the window that I am trying to click. Sometimes even the desktop isn't clickable. The panels in XFCE are also affected by the problem.
My external display is a Samsung TV connected to the 4337 dock's DisplayPort over a DP to HDMI cable. The setup worked properly on Windows 7, Windows 10 and Kali Linux.
I already tried changing the display settings, with no effect.
What could be causing the problem?
Update: Problem exists on Xubuntu 16.10 as well. It exists on both live-USB and installed systems.
Update 2: I verified that the problem exists also on Debian Jessie (with XFCE) and on CentOS 7 (didn't even have to install it - problem appeared already during the pre-installation stage).
Update 3: Noticed the same problem on Kali, but for some reason it's not happening as often as on other distros.