Well, not to state the obvious, but I accidentally changed my screen contrast when I was messing around in my M9 Setup. If you go into Setup mode and rotate the top left button until the 'Midi - Gate - Display' window appears, there's a control for the readout contrast in the top right rotary knob. I had inadvertently turned my contrast down - the colored backlights were still normal but the text was barely visible. Turning the Display Contrast button to about halfway brought it back to normal. Hope this helps.
