Theres been one little thing that has annoyed me for a very long time.
I use a MacBook Pro with a display and a keyboard and mouse. I use an Airplay speaker to play music from my Mac, but the volume keys on my keyboard only control the system volume and not the volume of playing music. This is especially annoying when receiving a phone call or having to quickly duck the volume.
Today I found a neat little download that makes it so much easier. In essence it makes the volume keys on your keyboard control the Apple Music app directly and to control the system volume you just hold down the CMD key whilst pressing those buttons!
Get it here: https://github.com/alberti42/iTunes-Volume-Control