I have been puzzled why the battery on my MP3 player is sometimes inexplicably flat and at other times goes on for ages without a recharge. Now I have solved it.
The Samsung YP-T10 doesn’t have a off switch; it times out after a certain period of inactivity which is adjustable in the system preferences. When playing music files, I stop (actually pause) the song using the centre touch button and that counts as inactivity. However, when using the FM radio, the centre button is a MUTE—so I have been leaving it on for days at a time, hence it is flat when I come back to it. The only way to stop the radio is to back up to the root menu using the top left touch button. This activity doesn’t stop ordinary music playing at all.