Hi. I was wondering if anyone else has had this problem. I'm using a Microsoft optical Intellimouse Explorer with my iMac, and sometimes I have to click a link in Safari up to 5 times before it responds with the blue progress bar going across the address. I hold the pointer completely still while clicking, and I make sure that I'm fully depressing the button, but there is no response. Again and again, there is no response. It is somewhat frustrating. Any help you can give will be appreciated. Thanks. 