private void FixSoundReference_Playback(int originalIndex, IWriter buffer)
        {
            var playback = _container.FindSoundPlayback(originalIndex);

            int newIndex;

            if (!_soundPlaybacks.TryGetValue(playback, out newIndex))
            {
                newIndex = _soundResources.Playbacks.FindIndex(c => c.Equals(playback.Source));
                if (newIndex == -1)
                {
                    newIndex = _soundResources.Playbacks.Count;
                    _soundResources.Playbacks.Add(playback.Source);
                }
                _soundPlaybacks[playback] = newIndex;
            }
            buffer.SeekTo(_soundLayout.GetFieldOffset("playback index"));
            buffer.WriteInt16((short)newIndex);
        }