I know this doesn't help your problem but you should consider using arrays and get rid of the timeout loop, onPlayerEnters will work fine.
PHP Code:
//#CLIENTSIDE
// Music
function onPlayerEnters(){
temp.saljiut = {
"crosscastle_1c10.nw", "crosscastle_1d10.nw"
}
temp.lystra = {
"crosscastle_1b05.nw", "crosscastle_1b04.nw",
"crosscastle_1c05.nw", "crosscastle_1c04.nw"
}
if (player.level.name in temp.saljiut) {
playlooped("armageddon-saljiut.mp3");
}
else if (player.level.name in temp.lystra) {
playlooped("armageddon-lystra.mp3");
}
}
Try placing the files in the music folder, then delete your filenamecache file, and reload Graal so it has to go through your Graal folder and files again.