Mouse Problem for KVM switch

Hi all,

I have used a KVM switch box to share a PS/2 mouse (without speedy wheel), keyboard and monitor for my two PCs. Recently, my original PS/2 mouse is broken down, and then I replace it with another PS/2 mouse with a speedy wheel embedded. However, after I plug this PS/2 mouse on the KVM switch box, The mouse cursor can't move and just stand still on the centre of the screen. When I right click the mouse, the pop up windows could be shown. Certainly, the mouse can be detected by the system successfully.

Now, do anybody give me hint for this problem caused?

Thanks in advance.
Athens Yan.