Bug description

When Audacity performs cloud project synchronization, some audio blocks may not be uploaded to the cloud. After downloading such a project Audacity behaves as described in #8004

Steps to reproduce

The steps to reproduce are yet to be discovered.

1. Upload a 2-3GB project with multiple tracks.
2. Apply destructive effects across all tracks
3. Sync with cloud, and edit the project during synchronization
4. Repeat a few times

Expected behavior

Project is synchronized without any data loss

Actual behavior

Some data is missing

Audacity Version

Audacity 3.7.x

Operating system

Windows

Additional context

No response