I see an inconsistency on updating some fields.
When i ripped this album
https://musicbrainz.org/release/ff935355-cf93-3697-bb4d-29c9c4200e32/disc/1
I had updated the metadata via jaikoz and, in musicbrainz, the credits were at the release level and not at the recording level. Furthermore, some data was not correct (for example the “bass” instrument and not the “bass guitar”).
Later I had changed the album in musicbrainz by moving the relationships at the recording level and changing the inconsistencies (“bass guitar” and not the generic “bass”).
After the last albunack update, I used Songkong to update the metadata but it did not delete the previous incorrect ones (and no longer present in Musicbrainz) but it seems to have added them to those already present previously