oh its a Casio WK 3000... something wrong with the keys.. instead of hearing only 1 note when i hit 1 key, it somehow produces other notes as well and it sustains by itself..
I used to own a K5000w but gave it up coz of the lack of backlight display. Although there is a company in uk http://www.midi-rakete.de/ that sells illumination foils for many keyboards that don't come with the backlight display, I was not courageous enough to "operate" on my keyboard. You might wanna try?