Premiere Pro audio out of sync? Causes and fixes

When Premiere Pro audio is out of sync, the cause is usually one of four things: variable frame rate footage from a phone or screen recorder, a mismatch between the sample rates or frame rates of your clips and the sequence, damaged conformed audio files in the media cache, or linked clips that have simply slipped apart on the timeline. The quickest way to tell them apart is to check whether the offset is constant (the same few frames everywhere) or growing (fine at the start, worse by the end). A constant offset usually means a slipped clip or playback latency. Growing drift points to variable frame rate footage or a clock mismatch between camera and recorder.

This guide assumes a recent version of Premiere Pro. Depending on your version, the options live under Preferences or Settings, so if something is not exactly where described, search for it in Premiere's help or check the release notes.

Step one: is it drift or a fixed offset?

Scrub to the start, middle and end of the problem clip and compare a hard sound, such as a clap or a door, with the picture.

• Same offset everywhere. The audio is, say, two frames late from start to finish. Look at slipped clips, audio hardware latency and sequence settings.
• Offset grows over time. In sync at the start, half a second out after ten minutes. Look at variable frame rate footage, sample rate conversion and separately recorded audio.
• Only during playback. The timeline looks right frame by frame, and the export is in sync, but playback feels off. That is a playback problem, not an edit problem.
• Only in the export. The timeline plays correctly, the exported file does not. Jump to the section on exports below.

Variable frame rate footage from phones and screen recorders

Many phones, screen recorders and video call tools record with a variable frame rate. The frames are not evenly spaced, so a clip labelled 30 fps can run slightly faster or slower in places. The audio, meanwhile, runs on a steady clock. Editors that assume a constant frame rate can place video frames at slightly wrong times, and the error builds up over the length of the clip.

Premiere handles variable frame rate media much better than it once did, but long clips can still drift, especially after speed changes, nesting or heavy trimming. To check a clip, select it in the Project panel and open its properties (right-click, then Properties). Recent versions can flag a variable frame rate there; if yours does not, a media information tool such as MediaInfo will show it.

The reliable fix is to convert the footage to a constant frame rate before you edit:

• Transcode with a tool that forces a constant rate. Free tools such as HandBrake offer a constant framerate setting. Choose the frame rate you intend to edit at.
• Use an intra-frame editing codec if you can. If your transcoding tool can write ProRes with a constant frame rate, you get files that are also easier to play back on a Mac.
• Replace, do not re-cut. If you have already edited with the original files, you can use Replace Footage in the Project panel to point the existing clips at the new constant rate versions, then check sync again.

Sample rate and frame rate mismatches

Most video work uses 48 kHz audio. Music files are often 44.1 kHz, and some recorders default to 96 kHz. Premiere handles mixed sample rates in the same sequence, which normally works fine, but mixed sample rates are worth ruling out when drift appears on specific files only.

• Check the sequence. In Sequence Settings, confirm the audio sample rate (48000 Hz is the usual choice for video) and the timebase match what you intended.
• Check the clips. The Project panel can show audio sample rate and frame rate columns. A clip that differs from the rest is your suspect.
• Watch for 23.976 versus 24. If 23.976 footage is interpreted as 24 (or the reverse), picture and real-time audio drift apart slowly. The same applies to 29.97 versus 30. Agree on one rate across the shoot and the edit.
• Convert stubborn files. If one audio file keeps drifting, convert it to 48 kHz WAV in an audio editor and relink.

Clear the media cache

Premiere stores conformed audio and other generated files in its media cache. If those files are damaged or out of date, clips can play with the wrong audio timing or with glitches. Clearing the cache forces Premiere to rebuild them.

1. Save and close your projects.
2. Open Settings or Preferences (the name depends on your version), then Media Cache.
3. Use the option to delete media cache files. Recent versions offer to remove unused files or all files; with projects closed, removing all is the cleaner reset.
4. Reopen the project and give Premiere a moment to re-conform audio before you judge sync.

Keep the cache on a fast drive with free space; a full or slow cache drive causes playback problems that feel like sync problems. If playback stutters in general, our guide to Premiere Pro playback lag on Mac covers the rest of that ground.

Fix a cut that is already out of sync

If the edit is done and you do not want to start over, there are several targeted repairs.

Linked clips that slipped apart

When linked video and audio move apart on the timeline, Premiere shows small red numbers on the clips: the number of frames they are out of sync. Right-click the number and choose one of the sync options. Slipping into sync changes which part of the source plays without moving the clip on the timeline; moving into sync shifts the clip itself. Pick the one that keeps your cut points where you want them.

To avoid this, keep linked selection on when you trim.

Separately recorded audio

For dual-system sound, where the camera's scratch audio and a separate recorder's audio need to line up, Premiere can sync by waveform. Select the video clip and the audio clip, then use Synchronize from the Clip menu, or Merge Clips, and choose audio as the sync point.

If the clips line up at the start but drift by the end of a long take, the two devices' clocks do not agree. Sync at the beginning, then find the offset at the end and stretch the audio slightly with the Rate Stretch tool or Speed/Duration until both ends match.

When only playback is out of sync

If the timeline is right frame by frame and the export is in sync, the problem is how you are hearing it.

• Bluetooth headphones and speakers add latency, which makes sound arrive late against the picture. Test with wired output or the Mac's built-in speakers.
• Audio hardware settings. In Settings or Preferences, under Audio Hardware, confirm the correct output device and try a different buffer size if your interface supports it.
• Dropped frames. If the picture cannot keep up, sound runs ahead. Lower the playback resolution or use proxies and check again.

When only the export is out of sync

If the timeline plays correctly but the exported file does not, look at the export settings and at the media itself.

• Frame rate in the export preset. Make sure it matches the sequence. Converting frame rates on export can cause stutter that reads as a sync error.
• Variable frame rate sources again. Some drift only appears when Premiere renders the whole timeline. Converting sources to a constant rate usually fixes it.
• Check the file in another player before assuming the export is wrong.
• Export a ProRes master first. If the delivery file drifts but a ProRes master does not, encode the delivery from the master. For export errors in general, see our guide to Premiere Pro export failed errors.

Moving the cut to another editor

Sometimes a sync problem shows up after a cut travels between applications through XML or EDL. Interchange formats describe edits, not media, so the receiving editor has to relink and interpret frame rates and timecode itself. Compare the imported sequence against a reference export from the original edit, at the start, middle and end.

If you export the sequence from Premiere as XML or EDL and import it into cinemaOS, the import produces a conform report, and the Bring a cut, hand it back tutorial shows how to read it: whether the media is online and the edits are preserved. Then play the sequence and check sync yourself at the start, middle and end. cinemaOS cannot open .prproj files directly, so the XML route is the one to use. Our guide to moving a cut between Premiere, Resolve and Final Cut covers what tends to survive the trip and what does not.

FAQ

Why does my iPhone or screen recording go out of sync in Premiere Pro?

Most likely because the file has a variable frame rate. The video frames are not evenly spaced while the audio runs on a steady clock, so small timing errors build up over a long clip. Converting the file to a constant frame rate before editing, then replacing the footage in the project, is the dependable fix.

Why is the audio in sync at the start but not at the end?

Growing drift means two clocks disagree. That can be variable frame rate footage, 23.976 footage interpreted as 24, or a separate audio recorder whose clock runs slightly differently from the camera. A fixed offset that does not change over time is a different problem, usually a slipped clip or playback latency.

Will clearing the media cache delete my project or edits?

No. The media cache holds files Premiere generates, such as conformed audio and peak files, and it rebuilds them when needed. Your project file and source media are not touched. Close your projects first, and expect the first reopen to take a little longer while Premiere rebuilds what it needs.