Q: I downloaded a song from itunes to my nano 7th generation. When i play the song i can't hear it with the head phones that came with the nano

Hi, i downloaded a song from Itunes to my ipod Nano 7th generation.  When i play the song on my Nano i can't hear the song with the head phones that came with the Nano.  what should do?

                                                                                     Thanks for your help.