We're still a little puzzled at this issue to be honest. DLSMusicDevice is built in to macOS, and Band-in-a-Box doesn't require having Garageband installed - this is why we can have a fresh install of Catalina work with Band-in-a-Box immediately.

In addition, I suggested the GarageBand fix to another customer, and it didn't work for him, so there are likely multiple layers to this issue.


I work here