I haven't looked at your code but I encountered a similar problem on a site I was building, the scrolling was fast in every browser except firefox. Turned out

I haven't looked at your code but I encountered a similar problem on a site I was building, the scrolling was fast in every browser except firefox. Turned out that firefox doesn't dispatch scroll events as quickly as the others, but I found a function which fixed the problem: http://blog.keithclark.co.uk/faster-scrolling-parallax-websites-in-firefox/ http://blog.keithclark.co.uk/faster-scrolling-parallax-websi... Might be irrelevant but I thought I'd drop this in, in case it was useful.