When i unpack my case which i stored in another room, i found my old iPod (1st Gen) which is still clean without any scratch on the body and it's still working, but it ran out of battery because i left it for almost one year. It was moved to another room when my room was prepared for my wedding last year. Then i completely forgot about it.
Since it's unpacked, all i need to do is to clean up the earphone first and then i can try to listen to the songs again. Some people said that 1st Gen iPod has the best quality in terms of sound quality since it doesn't have too many features in it, so Apple was focusing on the sound quality.