我正在尝试使用MediaPlayerAdapter和VideoSupportFragmentGlueHost播放视频，但出现此错误：

我已经尝试搜索错误代码的含义，但未找到任何内容。

这是我正在使用的代码：

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        final Channel channel =
                (Channel) getactivity().getIntent().getSerializableExtra(Detailsactivity.CHANNEL);
        final Server server =
                (Server) getactivity().getIntent().getSerializableExtra(Detailsactivity.SERVER);

        VideoSupportFragmentGlueHost glueHost =
                new VideoSupportFragmentGlueHost(PlaybackVideoFragment.this);

        MediaPlayerAdapter playerAdapter = new MediaPlayerAdapter(getactivity());
        playerAdapter.setRepeataction(PlaybackControlsRow.Repeataction.INDEX_ALL);

        String hash = User.generateHash();
        String videoURL = "https://" +
                server.getHost() + ":" +
                Integer.toString(server.getPort()) +
                "/viewsa/ch" + String.format("%02d",channel.getNumber()) + "q" +
                Integer.toString(1) + "/playlist.m3u8?dvr&wmsAuthSign=" + hash;
        mTransportControlGlue = new PlaybackTransportControlGlue<>(getactivity(),playerAdapter);
        mTransportControlGlue.setHost(glueHost);
        mTransportControlGlue.setTitle(channel.getName());
        mTransportControlGlue.setSubtitle(channel.getName());
        mTransportControlGlue.playWhenPrepared();
        playerAdapter.setDataSource(Uri.parse(videoURL));
    }

这是错误：

E/MediaPlayer: Should have subtitle controller already set
E/MediaPlayer: error (1,-38)
E/MediaPlayer: Error (1,-38)
E/MediaPlayer: error (1,-38)

我希望我的视频流能够播放。我究竟做错了什么？任何帮助表示赞赏！