Link - A.h.-start Fansub- Kuroinu Kedakaki Seijo Wa Hakudaku Ni Somaru 01.mp4

| Symptom | Likely cause | Fix | |---------|--------------|-----| | | Video codec not supported (rare for MP4) | Update VLC to the latest version; otherwise re‑encode with HandBrake to H.264/AVC. | | Audio out of sync | Variable‑frame-rate (VFR) source or subtitle timing mismatch | In VLC, enable Tools → Preferences → Input/Codecs → Synchronisation → “Desync audio” and adjust, or use Subtitle → Sub Track → Delay . | | Black screen / “unsupported codec” | Corrupt file or missing video track | Verify the hash (section 1) or re‑download from a trusted source. | | Subtitles show garbled characters | Wrong encoding (e.g., Shift‑JIS vs. UTF‑8) | Open the subtitle in a text editor (Notepad++, VS Code). Use Encoding → Convert to UTF‑8 and save. | | File won’t play on a mobile device | Device only supports MP4 with H.264 video & AAC audio | Re‑encode with HandBrake: Preset → Fast 720p30 (or the resolution your phone can handle). |

MPV also supports on‑the‑fly subtitle timing adjustments ( + / - to shift) and can be combined with / yt-dlp for streaming from legal sources. | Symptom | Likely cause | Fix |

[ ] Verify file size / hash [ ] Open in VLC → confirm playback [ ] Add external subtitles (if needed) [ ] Sync subtitle timing (Tools → Track Synchronization) [ ] (Optional) Hard‑code subtitles → HandBrake [ ] Rename file to a consistent scheme [ ] Organise in folder hierarchy [ ] Backup (7‑Zip + cloud/NAS) [ ] Test on secondary device (phone, tablet) [ ] Keep VLC/MPV up‑to‑date | | Subtitles show garbled characters | Wrong encoding (e