New media items added to library via a monitored folder will appear with missing metadata until the metdata is edited. The "missing" metadata actually appears to be in place, but just does not initially appear in the library. This seems to affect some of the newly added files, while some appear with the correct metadata in the library.
Repro steps:
1. Go to Preferences > Media Library > Folder Monitor
2. Ensure a folder is being monitored and all options are enabled, such as real time monitoring
3. Add a new folder to the monitored location, which contains some mp3s with correct metadata
4. Wait for the library to auto-scan, or restart WACUP to trigger a scan
5. SOME of the new media items will appear as blank entries at the top of the library
6. Right click a blank entry, and "Edit metdata"
7. Click in any field and then click "Update" (You don't need to actually change any values)
8. The media will now appear with correct metdata in the library
In the screenshot attached you can see three entries of a folder I added, two of them are missing metadata while one track appears correctly (censored as it's unreleased!). This occurs with every folder I add.