You can try to also clear the “Media Storage” application. But you will loose your playlists and stuff = DATA! So make sure you have some kind of backup just in case. What happened before the Music application stop working?
Update: I have no clue what Media Storage actually does. Maybe updating to the unofficial 4.4.4 could also help?
Maybe it depends on some other service … strange. It’s not a very complex app. So clearing the apps data and the media storage data does not help? Strange. Do you have your music on a SD card or directly on your phone? Else try vlc or other apps as a workaround for now.
For testing … can copy a song or two to the internal folder and remove the SD card? Afterwards clear all data (music and media) and restart the app? Just to see if the crash is caused by some issue correctly accessing the files? Just guessing here …
Thanks for the suggestion. Apollo works fine, it even integrates nicely with the phone function ie pauses during a call and can be controlled via the headset - that didnt work with VLC.
(I already had F-Droid installed.)