Its analog nature has also been the cause of a great number of problems. One problem was that all kinds of joysticks needed "calibration". This was true even for arcade-style ones. The reason for this was that no game controller and no joystick produced the same measurements each time. These depended on the exact way acquisition was made. Some of the worse designs even depended on the speed of the CPU. Also, all kinds of PC game ports suffer from electrical noise.