MAJORFailure Reference

Vidu Lip Sync Failure — Pre-Generation Risk Reference

Technical Classification

Audio-Visual Synchronization Failure

Audio-Visual Synchronization Failure on Vidu occurs when the model's lip articulation diverges from the expected phoneme alignment. Vidu does not generate audio natively (unlike Veo or Sora) — but talking-head prompts produce lip motion that should match a plausible speech pattern. When generated alongside externally-supplied audio (TTS, voice clone), the misalignment becomes severe.

How to identify this failure

✕Mouth open during silent moments, closed during speech in Vidu output
✕Lip shapes don't match expected vowel/consonant phonemes
✕Articulation collapses to a generic open-close pattern
✕Multi-character scenes — wrong character's mouth is moving
✕Lip motion freezes for 1-2s mid-utterance

Real generation examples

Prompt used

"News anchor delivering a one-minute weather forecast, professional set"

Failure observed @ 0:14

Lip sync drifted from word 12 onward, mouth froze at 0:14

Prompt used

"Customer service rep on a call, headset, office background"

Failure observed @ 2.1s

Mouth remained closed for entire utterance from 2.1s-4.4s

Documentation strength

If you need to escalate

HIGH — Lip sync failures on Vidu are recognized refund cases when the audio track and timestamp are provided.

AVA is a pre-purchase prevention tool, not a post-purchase recovery tool. Platforms generally do not guarantee credit refunds for output-quality failures; goodwill credits are at each platform's discretion. The strength rating reflects how well-formed your support ticket can be, not a promised outcome.

Prevention + documentation steps

01
Score your prompt before you generate
Run your prompt through AVA's pre-flight scoring against the Audio-Visual Synchronization Failure pattern. Green light = generate. Yellow/red = rewrite using the suggested fix before you commit credits.
02
Capture Generation ID + timestamp if it failed anyway
Find the Generation ID in the URL or share link. Note the exact time when the Audio-Visual Synchronization Failure first appears (e.g. "failure first visible at 1.2s"). Timestamped evidence is significantly stronger than a general complaint.
03
Use the correct technical term in your support ticket
Describe this failure as "Audio-Visual Synchronization Failure". This term maps to a recognised internal workflow in the support system and routes the ticket to the right team.
04
Submit via the correct support channel
Runway has no direct email intake. Pro+ plan: open the in-app AI Assistant (help widget bottom-right of app.runwayml.com), describe the failure with the technical term, attach evidence. Free/Standard plan: human support isn't available — your channel is Discord #community-help with @On Call - Moderators.

Frequently asked questions

Does Vidu produce its own audio?

No — Vidu generates silent video. Lip-sync failures occur when external audio is paired with Vidu output. The lip articulation should still match plausible speech; failure to do so is a support responseable defect.

How do I document a Vidu lip-sync failure?

Provide the Generation ID, audio track (or TTS source), and timestamps where lips diverge from the audio. AVA generates the comparison automatically.

Which Vidu prompts are highest risk for lip-sync failures?

Long talking-head clips (>6s), multi-character dialogue, low-light scenes where mouth contours are ambiguous. AVA flags these.

Score your prompt

Score your prompt against this failure mode in 30 seconds

Paste your prompt and the platform you intend to use. AVA returns a red/yellow/green score against this specific failure mode plus a concrete rewrite if the risk is high.

Install free All 105 failure modes

AVA Pro · founders' round

$50 for 6 months of unlimited scoring across all failure modes + personal failure-history dashboard. Locks in $13/mo grandfathered after.

Claim $50 founders