The same problem here, but I have found a way to make it work (actually there are two ways LOL)
- Remove one of the batteries. Believe it or not, the scroll wheel works perfectly when I remove one of the battery (doesn't matter which one). However, I don't know how long it will last since there is only one battery in operational.
OR
- Remove the batter cover and take out the batteries. Use a screw driver to loose the screw about 2 turns (for some reason I believe it was screwed in too tight). Put the batteries back and you are or set.
I can not guarantee that my methods will always work, but the fact is it's working for me ever since.