Ok, here it comes:
In Soldat, there should be an looping option. This gives you an ability to loop mp3 music in-game. Like only one song repeats in the round, when the map changes, the song changes. So, the same round, the same song. Like it? :P

No.
Why would you want to listen to the same song over and over?
Just switch through the songs everytime to the one you want.

doesn't it play the same song over and over anyways?

I think that looping is a good idea, because if you want a song for the round the round would feel more set.
But the MP3 player needs to be kinked out first.