First check the mouse settings in control panel. Tracking speed etc...
Then, of course, look through the settings of the game itself, for any mouse settings. But I know nothing of that game, haven't played it.
But all I can is maybe with the new fangled mouse, there is some controlling software that is setting a "profile" for a game, like what joystick software does. But if there is something like that, you'll see it in control panel.
Other than that, I can't really say what it might be!