I'm using the Microsoft Arc mouse on my Mac Mini late 2007 model and I notice that on occasion, that it won't register clicks especially within the interface of the system specifically closing windows or the close tabs buttons in Firefox, or Safari. It wil often take multiple clicks just to close tabs which is very annoying. I first had a basic Microsoft mouse and I never noticed the problem, only until I started using the Apple Mighty mouse it became an issue. This sounds stupid but can't my Mini handle my licking speed? Is it a graphics or RAM issue? Has anyone else had this problem?