If you want your software to run smoothly, you must test, and edit, and test, and iterate, and trim. And test. And when you have an operating system as ubiquitous as iOS, you better do this a lot. In fact, perhaps this is why Apple Music remains twitchy and buggy -- a small population of secret-bound testers guarantees only that you won't find everything, or even most things.
iOS 9 beta 3 is the latest iteration of Apple's forthcoming mobile update, and is the first to include Apple Music. The update was pushed to developers -- the people who make things like Angry Birds and Vuvuzela apps -- yesterday afternoon, which will allow coders to tinker with how Apple Music can be integrated into their own apps (or at least how to deal with it when their app is running).
As The Verge points out, the update also includes a toggle for sound quality -- no that doesn't include 'hi-fi' listening -- between the respectable 256kpbs and a lower fidelity. Currently, Apple Music users aren't given the option of forcing their cell phone connection to deal with the increased load of 256kpbs.