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Skills / Starter / Check audio sync

Starter Video & audio skill

Check audio sync

Check audio-to-picture sync at multiple points and identify offset, drift, variable-rate, clock, or routing causes.

Check the beginning, middle, and end before applying one offset.

When to use

  • Use after ingest, multicamera sync, transcode, remote recording, long takes, or export.
  • Preserve original timestamps, rates, and files before resampling or changing interpretation.

Procedure

  1. Record source devices, timecode, frame rates, sample rates, variable-rate status, duration, and timeline settings.
  2. Find a sharp visible and audible event near the start and measure offset.
  3. Repeat at the middle and end to distinguish constant offset from progressive drift or discontinuity.
  4. Compare camera scratch, recorder, remote local, platform, and reference tracks.
  5. Correct constant offset at the clip level; correct drift only after identifying clock, sample-rate, frame-rate, or dropped-media cause.
  6. Listen for phase, channel, pitch, edit, and time-stretch artifacts.
  7. Export a test and verify lip sync on target playback systems.
  8. Document corrections and retain the untouched source.