How to repair files identified as corrupted?
If the file in question is a MP3 file which is reported as corrupted or where the MP3 header cannot be read, chances are it is an MP4 file with a *.mp3 file extension. This often happens if online services, e.g., to download files from YouTube are involved. Changing the file extension to *.mp4 might solve the problem.
If the problematic file is a WAV or AIF file, re-saving the file with an audio-editing program like Audacity might repair the files. It's also possible to use ffmpeg via a user-defined tool from within Mp3tag
Please also listen to the end of the file to make sure the file isn’t truncated.