Digging a bit deeper I found that Spotify’s licensing prohibits the streaming or caching of two tracks simultaneously and their ToS states “You may not, and you may not permit any device or system used in connection with the Spotify service to, segue, mix, re-mix, or overlap any Spotify Content with any other audio content (including other Spoftify Content)”
Despite this, they have had their relationship with Algoriddim for around six years, so I wonder what has changed their stance now. Commercial pressures I guess.
Perhaps they could get a new license to cover this scenario and add an extra tier of subscription for DJs to help cover the cost. I would happily pay a reasonable amount to continue with the convenience and library of Spotify.
Feel likes they’re missing a commercial trick here and I wouldn’t be surprised if they lose a load of Premium subs over this.