Microtek innovations wireless keyboard/optical mouse combo

[frag79]

I bought one of these for $20, but I'm about to return it if I can't get it to work properly. It can be used with either a single usb for both keyboard and mouse, or two ps2 cables. When I try the usb method, the keyboard works fine, but the mouse pointer only goes up or down no matter which way I move it. When I use the ps2 method, the keyboard works fine, but the mouse pointer floats around the screen by itself. It only moves a few millimeters at a time, but it makes the mouse hard to control. I can leave it alone with the pointer in the middle of the screen and 30 minutes later, It will be on one of the far corners of the screen. Has anyone else had this problem?

Thanks,
Mike