I've upgraded my Ubuntu from 12.04 to 14.04 and now have some problems with system shortcuts. It's in such menus, as Launchers (Launch terminal), Navigation (Switch to another workspace), Windows (Close window). The problem one is that when I restart my computer (not after every restart, but after a few times) my shortcuts sets to default ones, so I can't change them permanently. Also, I've noticed, that change language shortcut also doesn't work normally. So, it may be the problem, somehow connected with system shortcuts at all.
I've read a lot solutions on that topic, but nothing helped. Maybe, somebody had the same problem and fixed it? Appreciate your possible help.