Official comment
Eryk,
It sounds like whoever assembled that file didn't put the title as:
Animals (Extended Mix)
...but instead has it as two separate fields, TITLE is set as:
Animals
...and the MIX NAME is set as:
Extended Mix
Here you can see an example of this with the mix not being part of the title field:

If this is the case with your songs and you'd prefer to have the mix name as part of the title field, I would suggest you use a tag editor to merge the two fields automatically, then refresh the tags in rekordbox.
For Mac, I highly recommend Yate, for PC, Tag & Rename.


