Hey @Piersy_B, offline storage does not seem to be possible with SoundCloud DJ. Their support page only mentions Virtual DJ and Rekordbox and djay‘s own FAQ page only mentions BeatSource and BeatPort as offline storages within djay.
Using a mobile also won’t help much here since the offline tracks are locked to their respective app and are not usable within djay so on mobile you also only have BeatPort and BeatSource supported.
There is a related feature request about this here: SOUNDCLOUD DJ Update
