[jmarshall]

Scanning that particular song placed in a folder by itself with default settings from Gotham gives 2 repeats for "John Mayer". When a lookup is done on each, one is John Mayer and the other is Frank Ocean. Reason is the song contains two musicbrainz_artistid's (one for John Mayer, the other for Frank Ocean), and a single artist field. Thus, by default we use the artist "John Mayer" but have disambiguated due to the two musicbrainz_artistid's. If you turn the setting "Override tags with online info" on, you'll get the two artists "John Mayer" and "Frank Ocean" listed.

I suggest you keep things simple. Move files you feel are being scraped incorrectly to a separate folder. Clear everything out and just scan that single folder. Ensure you get what you expect.

Cheers,
Jonathan