Here is a quick test you can do to help isolate the problem:
Switch the x- and y-axis connections from the trackball to the ME4. If the same axis is not responding, then your problem is with the ME4. If the problem moves to the other axis, then your trackball is the culprit.
I had a brand new Happ trackball that didn't work on one axis when I received it. After checking the continuity of the trackball wire harness, I found that one of the signal wires was broke inside the colored wire coating. I cut the wire and spliced it back together where the break was, and it worked fine after that.
Any "mouse" (desktop, spinner, trackball, etc) connected to your PC in Windows, regardless if it is PS/2, USB, serial, will act as the system mouse and allow you to navigate within Windows.