The trackpad on my ibook g4 has gone mad. It works sometimes and doesn't others with no rhym or reason. When it goes bad the curssor will either jump from one side of the screen to the other or not move at all. Sometimes I can olny move it up and down others only side to side. I've tried cleaning it to no avail. I have apple care but I know when I go into the store that it will work fine with no problems and that when I get back home all hell will break loose. Has anyone else had these issues or can offer some advice??