Some users have asked which metadata fields on their audio files are updated by rekordbox and which are not. The answer depends on what filetype you are using, so here's the list:
AIFF (ID3V.2.4) / MP3 (ID3V.2.3)
Title TIT2
Artist TPE1
Album TALB
Genre TCON
Comments COMM
Track Number TRCK
Disc Number TPOS
Album Artist TPE2
Composer TCOM
Lyricist TEXT
Year TDRC
Mix Name TIT3
Remixer TPE4
Label TPUB
Original Artist TOPE
Key TKEY
Artwork APIC
WAV (RIFF INFO)
Title INAM
Artist IART
Product IPRD
Comment ICMT
Genre IGNR
M4A (AAC type only)
Name ©nam
Artist ©ART
Album ©alb
Composer ©wrt
Comment ©cmt
Genre gnre/©gen
Release Date ©day
Track Number trkn
Disc Number disk
Cover Art covr
Album Artist aART
Comments