From Daniel Fisher, Sweetwater's Chief Soundware Engineer and Kurzweil Personality Disorder Expert:

"If your Kurzweil K2xxx ever gets hit with a weird gamma ray from another galaxy, and just won't behave itself, the first thing to do is to try a Hard Reset. This can be done from either the Master Page or, while powering the unit on, hold down key numbers 1, 2 and 3. Then press Hard Reset, turn the unit off, and turn it back on. Normally this will correct any problems (ray-induced or otherwise). If this should fail, one last resort: Take all three AA batteries out of the unit for two or three hours. Re-install the batteries (with correct polarity, you did check when you took them out, right?), turn the unit on, and the unit will Hard Reset itself. Doing this should result in a happy, docile, well-adjusted Kurzweil."