Help! Blank screen!

[nofarewell]

Please help me, I'm desperate! Or tell me if you've ever experienced such a phenomena. It's been a day now that my player turned blank - no themes, only the dark-shaded backlight can be seen. It's working though, the touch-sensitive buttons are reactive, fully functioning, and it plays music, can record sounds, etc... but I can see nothing of what's going on. What should be done? Can it be a software problem, or is it hardware - nature? I'm not aware of any physical encounter which would have caused such a thing and really depressed about it...