When adding a music file with numbers in the name, a Track Number is extracted and added to the metadata as the original value. If the number is at the beginning of the file name, the Title original value is also truncated at the beginning.
These changes get saved and corrupt the metadata. If you're renaming files, the resulting file name is also changed.
I have renamed the file to remove the number to verify that the problem of the metadata change goes away. Thus, proving the metadata change is a result of the numbers in the file name.
I have reset all options to the default. I have uninstalled, deleted "AppData\Local\MusicBrainz" and "AppData\Roaming\MusicBrainz", and re-installed. (Selecting "Remove settings and personal data" during the uninstall appears to have no effect.) The problem is there on a clean install.
I have enabled debug logs and see nothing related to this action.
I have disabled all of the pre-installed plugins to determine if one is responsible, but no change. (BPM Analyzer will not disable.) (Also, attempting to uninstall a pre-installed plugin
I have attached to example files.
I can find no documentation or reports of this action.
Harry Chapin is robbed of all his bananas.