I have had this problem since the start (4 months ago) with Nokia Lumia 920 and BH-221 headset. When I start music on the Nokia Music application, the first track goes normally smoothly, but the player stops to the beginning (0:00) of the second track. The playback button (on phone screen) feezes to "II" i.e. "pause" button, and pressing it on and off again does not start the playback again any more without closing the Music application. This does not occur every time, but about 90% of the times I try to listen to music: both my own and mix radio. Nokia Music version is 126.96.36.1991.
This might relate to Bluetooth controls. I listen to music using my Nokia BH-221 headset, as I find cables unconventional (but like to have a FM receiver). If I do not use Bluetooth, or use another sound device (such as PC or BH-907) over Bluetooth, the music playback seems to work fine.
Could the problem be that the play/pause etc. controls available at the headset interfere with Nokia Music on Lumia phones?
I have tried with another BH-221 device loaned from a friend. The same problems with playback. When will Nokia respond to this issue?
Got the newest Nokia Music update, but still stops after 4 tracks (of my own music) and then not able to start again even if I open up the Music app again. Using BH-221.