Audio Playback Error 1609891835 After Downgrading Project

I’m getting “Error Code: 1609891835 - Premiere Pro could not start audio playback” on specific timelines after downgrading a project from v26 to v25.5.

Here’s what I’ve done so far:

1. Deleted all media cache files from Premiere and ~/Library/Cache

2. Changed playback device to Adobe SRT in Preferences

3. Tried different sequence settings (ProRes, H.264)

4. Reinstalled audio drivers

The issue only happens on sequences edited in v26, even after downgrading. Video plays, but audio fails with the error above.

System:
macOS Sequoia 15.3.2
MacBook Pro M3 Max, 48GB RAM
Premiere Pro 25.5

Any help troubleshooting this would be great—I’m unable to edit my recent work.