Autotagger sometimes doesn't detect duplicates

Greetings,

Firstly thank you to the dev for this awesome software!

Sometimes, when importing an album with the autotagger, it will be an album that I already have in the library, and the autotagger will let it in. Some rapid fire observations:

  • Inspecting via mp3tag, all the tags are exactly the same.
  • In some cases, the files are different – mp3 vs. flac.
  • In other cases, the file types are the same.
  • Always, these albums are located in different paths.
  • Always, these albums are downloaded at different times, via different sources.

Any thoughts on why this happens? I would love to know how duplicates are detected on import.

Many thanks in advance.