Mouse jumping

Hi, Im kinda new Multiboxer and just getting ready to start leveling. But I have already faced a problem. (I am using 3characters, maybe fourth coming. I have my main char on my 22" Wide. And 2other chars on my other display).
I normally can just use my mouse on both screens, just by dragging it to right from my main screen. But time to time my mouse starts bugging, and everytime I try to drag it to my alt screen. It jumps back to main screen around 5cm from the edge.
How to fix this? Its kinda annoying when I have to make macros or tweak the addons/settings.

You will need to be more specific regarding the amount of computers and the utilities you use.