I have a customer who owns the Maxxus RunMaxx 9.1 treadmill. The speed display shows the error message E-01. According to the operating instructions, this means that the friction of the treadmill is too high or the speed sensor is dirty. The speed sensor was indeed very dirty and has been cleaned. However, the error message still appears, even after switching on and off. Does anyone know whether it may be necessary to reset the control unit with a specific key combination? Or is there another problem? Thanks for any feedback