When running various programs (as I write this, with Chrome & Evolution) I move my mouse to the title bar to access the menu. The menu only seems to appear if I target the buttons to the left. When I move the mouse off the buttons (but still on the title bar) to select a menu then most times the menu disappears. It would seem this only happens on of my displays (of which I have 2) and it is the display that has the unity menu on it. Any ideas?