下了個mkv 電影，預覽圖明明是有字幕的，
但我用MPC HC 看，卻完全沒有字幕.....


檔案屬性：
Video: MPEG4 Video (H264) 1280x720 23.98fps [Undetermined (Video 1)]
Audio: Dolby AC3 48000Hz stereo [Undetermined (Audio 1)]
Subtitle: SubStation Alpha [Undetermined, 中英特效字幕1 (Subtitle 1)]
Subtitle: SubStation Alpha [Undetermined, 中英特效字幕2 (Subtitle 2)]
Subtitle: SubStation Alpha [Undetermined, 英文字幕 (Subtitle 3)]
Subtitle: SubStation Alpha [Undetermined, 中文字幕 (Subtitle 4)]