Premiere Pro 26.2.0 corrupts WAV source offsets after reopening a project. Cut external audio loses synchronization when 50 fps footage is combined with WAV files using 25 fps timecode.

I would like to report a reproducible issue that causes externally recorded WAV audio to lose synchronization after a Premiere Pro project is saved, closed, and reopened.

Environment:

• Adobe Premiere Pro 26.2.0, Build 65

• macOS

• Editing and delivery sequence at 25 fps

• Camera footage recorded primarily at 50 fps

• External multichannel WAV recordings at 48 kHz

• Sync map generated in Tentacle Sync Studio and imported through Final Cut Pro XML

Problem description:

The imported synchronization sequence used a 50 fps timeline, while the external WAV master clips contained 25 fps timecode metadata.

Immediately after importing the XML, the camera and recorder audio were correctly synchronized. Cutting and editing the synchronized material also worked correctly during the active Premiere session.

After saving the project, closing Premiere Pro, and reopening it, the cut WAV clips referenced incorrect positions inside their source files. Their timeline positions and visible edit points remained unchanged, but their Source In/Out offsets changed. Consequently, the clips played audio from different parts of the WAV files and no longer matched the camera audio.

This is not a timeline slip, linking problem, or media-cache issue. The incorrect source offsets are saved in the Premiere project and are also visible when the damaged sequence is exported to Final Cut Pro XML.

Reproduction steps:

1. Create or import a 50 fps synchronization sequence.

2. Place 50 fps camera footage and external WAV files with 25 fps timecode metadata in the sequence.

3. Confirm that the camera and recorder audio are synchronized.

4. Cut the synchronized WAV clips into multiple segments.

5. Save the project.

6. Close Premiere Pro.

7. Reopen the project.

8. Compare the WAV clips with the camera audio or inspect their Source In/Out values.

Actual result:

After reopening the project, cut WAV clips reference incorrect source positions. Some Source In values become negative, some clips reference audio far from the intended position, and source durations no longer correspond to timeline durations.

An XML exported from an affected sequence may contain:

• negative Source In values;

• Source Out values much longer than the timeline segments;

• mismatched in, out, pproTicksIn, and pproTicksOut values;

• different source ranges for clips that should be contiguous.

Expected result:

Saving and reopening the project should preserve the exact Source In/Out offsets of every cut WAV clip. The clips should continue playing the same source samples and remain synchronized with the camera audio.

Additional verification:

A basic import-save-reopen test without cutting the WAV clips remained correct. The corruption appeared after the synchronized WAV material had been cut.

I also confirmed that:

• clearing the media cache does not repair the offsets;

• the source WAV files remain valid and unchanged;

• relinking the media does not resolve the issue;

• Sync Lock and Linked Selection are unrelated;

• the incorrect values persist in exported sequence XML;

• multiple mono channels belonging to the same recorder file are affected.

Workaround:

Converting the synchronization sequence to 25 fps before editing prevents the issue, provided that native source coordinates are preserved:

• sequence timeline positions are converted from 50 fps to 25 fps;

• camera Source In/Out values remain in their native source rate;

• WAV Source In/Out values remain in their native source rate;

• only the sequence timeline coordinates are converted.

Recovering an already edited sequence requires reconstructing the WAV Source In/Out values from the corresponding camera clips and the original synchronization map.

Impact:

This is a serious data-integrity issue. The project opens without an error message, and the clips remain visually positioned on the timeline. The corruption may therefore remain unnoticed until playback, mixing, or export. Manually rebuilding the audio offsets in a long-form project is impractical and creates a risk of delivering incorrectly synchronized audio.

Please investigate how Premiere Pro serializes and reloads audio Source In/Out values when:

• the sequence uses 50 fps;

• camera sources use 50 fps;

• external WAV sources use 25 fps timecode metadata;

• synchronized material is cut;

• and the project is saved and reopened.

Kind regards,

Jakub Rolka