I have just finished a battery test on my S9...
I have had the S9 for a week and it has gone through 3-4 charge cycles. Playing music at 192kbps for about a couple of hours and then deciding to test the battery life, I stopped playing the 192kbps tracks and began playing 128kpbs (a quarter of the battery had dropped by the time I started playing the 128kbps tracks). The screen was off, volume at 14, eq set to normal. I got 40 hours of audio playback out of the player. I am happy with this, but was wondering if I shouldn't be, and if my unit is defective for not giving me closer to 55 hours of battery life?