If you can't play audio files with rekordbox, check if the following applies:
- The file format is not supported by rekordbox.
- Only limited applications can play the audio file: e.g. the audio file was downloaded from Apple Music etc.
- The location of the audio file has changed.
- The music file is damaged.
For details, see "Management" and "Music files that can be loaded and played (file formats)" in the rekordbox Instruction Manual.
You can read the rekordbox Instruction Manual [here].