(i) Some devices randomly restart.
(vii) The screen does not refresh automatically for some reason. If the screen goes off (battery saver) when you wake it up it will show for a couple of seconds exactly what it was showing before it went to sleep. So if the time was 14.50 then and is now 16.30 it will initially show 14.50. Or if you are listening to music it will show the song details of the song that was playing before the screen went off.
(iii) Some album art do not show even though embedded.
(iv) Tracker which updates media file info is very often defective. You can add media files and they not show up in the media player for a week.
(vii) Currently no equaliser though I don't see much point in an equaliser but just be aware there is none in the media player.
(viii) The play button on the media player widget does not work for some.
(ix) No way to stretch to full screen in the default media player (though mplayer a third party app will do so).
(i) There is no easy way to search your emails.
(v) For some it randomly goes to speaker mode whilst you are on the phone.
(i) If playing video I cannot receive calls.
(ii) Sometimes the phone rings with a blank screen for a few seconds so no way to answer the phone. I know a few others have had this issue but not sure how wide spread it is.