Lip-sync error
Sometimes the dubbed audio finishes successfully but Lip-Sync on top of it fails. You'll see a Failed status on the Lip-Sync card on the dub detail page — but the dubbed audio version is still ready and watchable, just without adjusted mouth movements. Lip-Sync failures are almost always a video issue, not an audio issue.
What "Lip-Sync failed" means
The dubbed audio is finished — you can publish it as-is
The on-screen mouth movements were not adjusted to match the new language
Lip-Sync is billed separately (1 credit per started minute, per language). A failed attempt is not refunded automatically
Common causes
No face detected in the video. Animation, motion graphics, screen recordings, product videos without a presenter, and voice-over-only footage have no face for the model to track. This is the single most common cause.
Face isn't visible enough. The model needs to see the speaker's mouth clearly. If the camera is far back, the speaker is in profile, or the mouth is obscured (microphone, hand, food, glass, mask), Lip-Sync can't find what to adjust.
Resolution is too low. Mouth detail at very low resolutions (e.g. 320×240) is too small to work with reliably.
Heavy motion blur. Fast movement, shaky handheld shots, or heavily re-compressed uploads blur the mouth area.
Too many faces in frame. Crowd shots or multi-face frames are hard — the model loses focus on a single speaker.
Animation, screen captures, or stylized faces. Lip-Sync is trained on real human faces. CGI characters, screen recordings, and cartoons typically fail.
What you can do
Publish the audio-only version. The dub is still complete and exportable.
Re-frame and re-upload. If the speaker was off-frame or too small, crop tighter on their face in your editor before re-uploading. A face that fills 20–40% of the frame works best.
Skip Lip-Sync for content that doesn't need it. For voice-over content, screen recordings, or B-roll-heavy videos, Lip-Sync isn't adding value — see When should you turn on lip-sync? for the decision framework.
Contact support
If a process fails, please do not try to trigger the dub or Lip Sync again. In almost all cases, simply re-starting the process without changing anything will result in the same error, as the issue is usually related to a specific file attribute or a processing conflict.
When to contact support
Failed Lip-Sync can't be retried from the UI today. If Lip-Sync fails on a video where the speaker is clearly visible, well-lit, in focus, and high resolution, write to hello@dubly.ai with:
The dub link
A short description of what's on screen for the speaker (close-up, wide shot, multi-speaker, etc.)
We can investigate why the model couldn't process it and retry on our side.