There’s beta support for streaming audio, it may be worth trying:
var vorbisFile = VorbisFile.fromFile (Assets.getPath ("audio.ogg"));
var audioBuffer = AudioBuffer.fromVorbisFile (vorbisFile);
var audioSource = new AudioSource (audioBuffer);
audioSource.play ();
If it’s stable, we can wire the “music” path up (probably?) to using streaming audio instead of loading into memory completely