Richard, my old kn2000 screen is fading also but not to the extent that it cannot be seen. It also changes with time after I turn the keyboard on. I believe that there are only two possible causes for this behavior, 1) the LCD screen itself is dying, and 2) the power supply for the screen is acting up.
I haven't tryed to fix mine but perhaps I will someday. Just hope that it is the power supply because that is fixable - the LCD screen is not and there are probably no replacement parts available except to buy a used kn2000 with a good screen.
I wish that weren't the case because the kn2000 is a great instrument and sounds sweet. The only reason that I went to the kn7000 was because of the terribly slow loading time of the floppy disk on the kn2000.
Walt