The problem appeared after me finishing the Dragonborn DLC mainquest by using the console command player.setav (because the last encounter is ridiculously buggy).
I did not notice the music at first but after 20-30 minutes of constant battle-music it started getting tedious.
The problem apears to be the game thinks I'm still trying to murder the boss, since the quest is not actually completed.
Now I've tried a couple of methods of geting rid of music mentioned in other forum posts (such as player.kill and going to jail etc.) but nothing seems to work.
I regretably have no save files left from before the bossfight so I cant undo what I've done.
If anyone has any ideas for tagging the quest as complete or stopping the music otherwise, I'd be forever in debt.
Because as stands now I cant keep playing with music or it will drive me nuts.