[R.O.D.]

Yesterday, i bought my mp4 nano like player. I uploaded video on it following the usual procedure: Everything allright. Then I upload music. When i try to listen to music, it makes me listen only the frst song, then, whe the song finishes or i change song pushing the-> buttn, it stops then resets... What do I have to do? Firmaware change? answer me, cos'im goin crazy!