Boardingmusic and announcements are failling to play

I am trying to create and play some personal music and announcements for my own VA livery. But I can't get this out.
In the VA livery I created 2 folders; announcement and music.
In the music folder I placed a few WAV files and in the announcement folder I placed the other sound files AND the announcement.msg file.

When loading the script, the correct announcement file is loaded (I adjusted the start text) but the music and announcements are not played.

Do the music files require a special codec or adjustment to hear them?
where should the sound fragments be placed and do they need a certain codec or setting?
If you know the answer, will you tell me how I can solve it? My gratitude!