I think the following newly added snippets of code that gives the scroll by page feature is taking focus away from the mousewheel. What happens is that you're happily scrolling away, then it will just freeze, then you have to click on the page to get it to work again. I adblocked the following code and it seemed to fix it.
Code:
www.cyclechat.net##LI[class="AdvUp"]
www.cyclechat.net##LI[class="AdvDown"]