Why won't it shut-down?

I got this Creative zen mp3 player, and up to now it's been working fine. It's a 20g with a 24 hour battery life, but today after recharging it, it simply wouldn't shut down. I mean whats the problem, why won't it shut down. i tried to reset it and it wouldn't work, so someone please tell me what's the deal. Please help!
Thank you for any response.

Let it fully discharge then re-charge it.Meanwhile,I`ll try to think of something else.