Scroll horizontal in the mixer

Hi
I struggle a bit with scrolling horizontal in the mixer in both Cubase and Nuendo. I have to place the cursor on the faders and use shift+scroll wheel on my mouse to make it work. But how come that the normal horizontal scrolling isn’t working in Cubase & Nuendo? Why do I have to move the mouse down to the faders? What’s the idea?
Regards MUSICMIND