anchor.diff:        sound,
         tag,
         loop,
  -      startTime,
         volume,
         pitch,
         pan,
  
positive.code: 
        // Prepare sound, then play it
        _prepare(playingSound).then((_) {
          playingSound._player.ptr.seekTo((startTime * 1000.0).toInt());
          playingSound._player.ptr.start();
        });
  
  
negative.code:     this.sound,
      this.tag,
      this.loop,
      this.volume,
      this.pitch,
      this.pan,
  