code: public void add(int position, SoundCloudTrack track) {
          if (mCurrentTrackIndex == -1) {
              mCurrentTrackIndex = 0;
          }
          mSoundCloudPlaylist.addTrack(position, track);
      }
docs: Add a track to the given position.
  
  @param position position of the track to insert
  @param track    track to insert.