sansa fuze clicking noise while playing music

I just bought a sansa fuze 2gb version 1.  I found that, while playing music,  the player has a click noise, initially only can be heard between songs. After playing a while,  the click noise would not stop even after the music start to play. The problem will gone if I power off /up the player once, but not for very long, the noise will come back. I tried the latest firmware and several headphones, nothing can solve the poblem. I am wondering if this is a hardware fault?  

Are you sure the headphone plug is fully inserted? When the player is new, it takes a bit of force to get the plug fully inserted.