I bought a Kensington optical mouse-in-a-box pro at CompUSA. It worked fine for a month or so, but now, everytime I try to single click on anything, it automatically double clicks. It is extremely annoying especially when web browsing. I have changed the double click speed in the control panel. I have tried the mouse on two of my roommates' computers, and it does the same thing, so I don't think it's my puter. They both run different operating systems than I do, so I don't think it's software. I just want to know if anyone's had the same problem, and if they've found a solution. I contacted Kensington support, but haven't heard anything back yet.