I purchased a Logiteck Trackman Wheel Trackball some months back and have used it since. It was great at the start. Perhaps the only problem was that it moved so fast it was hard to control. Now I have the opposite problem. Whereas before a light flick of the thumb would send it from one side of the screen to the next, it now takes several hard pushes with the thumb. I regularly clean the bearings that support the ball and cleaned the ball on several occasions with soap and detergent. It makes little difference. I've got to the stage where if this cannot be fixed I'll get something else it's that annoying.
Any suggestions on how to fix the problem. If not, does anyone use a trackball type mouse that does not have these problems?