Which file formats can I play?

The application loads and plays the tracks.
Currently, MP3, WAVE, AIFF, and m4a files are supported, depending on the application.
Tracks downloaded from Apple Music are not supported.

rekordbox supports FLAC, etc., however this may change due to software updates.

For the latest information and details, refer to "Music files that can be loaded and played (file formats)" in the rekordbox Operating Instructions.
You can read the rekordbox Operating Instructions [here].