gistfile1.js

// https://developer.mozilla.org/En/Using_audio_and_video_in_Firefox#Media_events
// https://developer.mozilla.org/en/XPCOM_Interface_Reference/nsIDOMHTMLMediaElement

var Sounds = {
  sounds: {},
  errors: [null, "ABORTED", "NETWORK", "DECODE", "SRC_NOT_SUPPORTED"],

  register: function register(sounds) {
    var errors = this.errors;
    for (var i = 0, l = sounds.length; i < l; i++) {
      var audio = new Audio();
      audio.autobuffer = true;
      audio.autoplay = false;
      audio.src = sounds[i].src;
      audio.addEventListener("error", function(event) {
        throw new Error("MEDIA_ERR_" + errors[audio.error.code]);
      }, false);
      audio.load();
      this.sounds[sounds[i].id] = audio;
    }
  },

  play: function play(id) {
    var audio = this.sounds[id];
    if (!audio)
      throw new Error("The id is not registered yet");
    audio.play();
  },

  pauseAll: function pauseAll() {
    for (var i = 0, l = this.sounds.length; i < l; i++) {
      this.sounds[i].pause();
    }
  }
};