Hi @hyunzlvr
Here is the way I do this. In your first scene you could create an entity that persists between scene changes and add a sound component.
let entity = new pc.Entity();
entity.name = 'Persist';
this.app.root.addChild(entity);
entity.addComponent('sound');
Later you can reference the sound component like this
let sound = app.root.findByName('Persist').sound;
sound.volume = 1.0;
In the dev tools console you can see the entity named “Persist” that was created. It lives outside if the current scene which is the one named “Root”