I use Spotify Connect from all of my devices at home, mostly the one that is closest to me at the moment. I´m used to change the volume independent of what device I´m using (iPhone, Apple Watch, iPad, Macbook Pro) and that has worked flawless until a couple of months ago (2-4 months I believe).
If I now try to change the volume from my MacBook Pro while using Connect I can only change it with the slider. The keyboard doesn´t work any more. The app indicates that the right key is pressed, but nothing happens. If I shut down Connect and instead play from speakers of my MacBook I can change the volume with the keyboard.
Like I said, this has worked perfect before, but not any longer.