get hasAudio() {
    // Assume yes for all non HTML5 (as we can't tell...)
    if (!this.isHTML5) {
      return true;
    }

    if (this.isAudio) {
      return true;
    }

    // Get audio tracks
    return (
      Boolean(this.media.mozHasAudio) ||
      Boolean(this.media.webkitAudioDecodedByteCount) ||
      Boolean(this.media.audioTracks && this.media.audioTracks.length)
    );
  }
Check if the media has audio