|As you probably know, when you press the scroll button it activates a switch. Most likely the switch is playing up. Try the mouse on another computer and/or try another mouse on yours.|
It is possible if you unplug the mouse and activate the button a number of times and quite firmly it will cure the issue, at least for a while. Sometimes you can put packing on top of the switch inside to compensate for wear - ie, it is not always pressing down firmly enough on the microswitch. However, as a replacement mouse is inexpensive it is probably not worth the effort of fiddling around inside it.
Always pop back and let us know the outcome - thanks
message edited by Derek