not a classic mistake, but a annoying bug: when the device is locked and someone calls and i fail to accept or reject the call, the phone locks itself again and the media player starts playing the currently selected song. d'oh.

very funny when you have your device set to silent-profile and someonce calls you and you decide to not react to the call on purpose... (i have the silent-mode set so that it still vibrates).
no use in silent-profile when the media-player starts playing out of nowhere.