I bought the mac mini 4go ram 2,53GHz model. t began to have issue with the mouse, principally in the Finder,The mouse would go crazy, scrolling through the toolbar and the folders/files within a window. Starting fro left and scrolling right to stop at the file on the extreme right of the folder. Also the left click freezes up and can sometimes only open a file using right click and clicking on Open. completely re-installed the system from the install discs but the same fault re-occured.Anyone have any idea as to what is happening??