I tried to set up Ubuntu 13.10, but there are massive focus problems which make it unusable. It don't seems to have something to do with Unity where I found something about focus problems in the web.
While the installation process the first problems happened: sometimes I was not able to press a button with the mouse. In this case I took the keyboard.
But when the window manager is started, Ubuntu gets unusable for me. Sometimes the focus seems to stick in a window. When this is the case, I can move the mouse over an other window, but I am not able to set the focus in it - it stays in the other window. Also if I use "alt-tab". Sometimes it even happens that focus of keyboard sticks in one window and focus of mouse in an other.
The strange thing is that this happens in 8/10 boots. So not every time, but most of the time.
I already tried to use Gnome desktop because I thought it might have something to do with unity, but it was the same there. MS Windows works without problems on this hardware.
I found a very similar question here with Ubuntu 12.04. I also use Chrome so it might be related to it. But for me it happens with all windows if the problems start: Mouse and keyboard focus problem
Have you some ideas? Did you already hear of such problems? What logs might be interesting?