OS 10.9.1, new iMac. Smart mouse. Sometimes, most of the time actually, when I just start Safari up, my first touch of the mouse sets off a visual explosion and the window blows up like a balloon. I went into the System Preferences>Mouse>More Gestures and played with it. But it still happens. The type font swells from normal to about 18pt. What can I do? Get a different mouse?