The file is a legacy installer for rekordbox 5 , a professional DJ software developed by Pioneer DJ (now AlphaTheta).
Downloading files with this exact name from third-party sites puts your computer at high risk of malware, ransomware, and identity theft. rekordbox-5.8.5.0001-Premium.dmg
Many older Pioneer DJ controllers act as a physical key. If you plug a compatible controller (like the DDJ-400 or DDJ-800) into your Mac, Rekordbox 5 will automatically unlock Performance mode for free. rekordbox-5
But her playlist was missing one track.