Monster and music issue

[Rownbear]

Another question regarding amb_music. I can't get this script to play off the music, as i'm tired of the leveleditor sounds system, you cant have multimple ambience sounds. So I can't get this to play

AddEntityCollideCallback("Player", "MusicAreaSewer1", "SewerMusic", false, 1);

void SewerMusic(string &in asItem, string &in asEntity)
{
StopMusic(2, 1);
PlayMusic("ambience_sewer_drip.ogg", true, 1, 2, 1, false);
}
***(OnStart Is in my script)