Something new in 8.4: Battery Usage shows Music using 6% of battery in last 24 hours ("Low Signal"); and 2% in last 7 days ("Background Activity"). I never use the app, and even have Show Apple Music switched off in the Music settings (note: I never even joined the Apple Music trial). There is no option to turn off Background App Refresh for Music. This sucks. I left Android (in part) because of stuff like this (processes running in background, eating battery). EDIT: I manually "killed" the Music app by swiping it away in the task switcher (it was still there from when I opened it briefly to check things out after the update). Will report back if that makes a difference over the next 24 hrs.