Help! My dock has suddenly stopped responding correctly to the mouse cursor. I have the dock set to automatically hide & show. Now, when I move the mouse over the dock area, nothing happens. I have to click in the bottom of the screen to get it to come up and click to make it hide again. A similar problem is happening with menu items. When I click on a list of items, if I move the mouse cursor over the arrows that move the list up and down and expand it sideways, nothing happens. This seems to be the same on all menus in all programs. I have a logitech wireless mouse which I've been using for years without any problems. It works normally on my other Mac so I don't think it is the mouse that's playing up. Anyone know how to fix this?