Scrolling with infrared type mouse using the scroll wheel "windows 7" has a dead spot and wont scroll, however If I depress the wheel for auto or mouse movement scrolling application it scrolls and then once the page is moved at all it will scroll with the manual wheel once again. Would cleaning inside possible fix it or get a new mouse, or What causes this and how to fix it?... Death Adder model# rz01-1005...3500 dpi,,3.5G infrared sensor. It has worked fine for years and nothing new added to pc. that I know of and no other strange behaviors.