The "mouse" button underneath the trackpad on my MacBook (non-pro) has recently started acting up. It's entirely functional, but the mechanics of pressing it have really gone nuts. If you press it at the very top, it's slightly more of a push to depress it, and sometimes makes a loud click. If you press it at the very bottom, it's completely silent, depresses slowly and very shallowly - as in, you only have to depress it about 3/4 of a mm for it to register a click. I'm selling the bloody thing soon, and I haven't had it 3 weeks. Any idea how I can sort it out? I'm in the UK and ordered online, so there's no Apple Store or reseller who will provide me with any guarenteed support or anything. Any ideas?