So I just got a 3g nano and its great, but here is what happens I dock it and the screen dims (good) and im listening to music, about 3-5min in the screen lights up again it displays "fully charged" along with the charged battery icon and my music stops playing. I then have to push play again for the music to start (continues right where it left off), but wait another 3-5min and this happens again. Any ideas guys?