I have a big concern regarding the new volume handling in iOS.

Now in Spotify-iOS when Spotify is playing somewhere else (on my Mac for instance) it will still have iOS show playback controls for Spotify which is very nice but here comes a few problems:

1. Listening on Mac then plug in phone:
   When I listen to Spotify on my mac and plug in my iPhone to a Lightning dock connected to power and my receiver as well it will switch to iPhone. 
   Most of the time I just want to charge it though and don't want to switch the input on my Receiver to my Mac. It is okay if it switches when I am in the Spotify app but please not when the device is not or even locked.
   
   
2. Listeing on Mac (stopping,) then continuing on iPhone:
   When Listeing on Mac the volume of Spotify there is mapped to the MusicVolume on iPhone, meaning when I switch to iPhone it will start playing at full Volume which is annoying
   
   
3. Listening on Mac via Bluetooth Headphones:
   Listening on a Mac (or Computer) via Bluetooth headphones (which can connect to multiple devices and are also connected to my iPhone) going away, so connection breaks. Walking back brings back connection to both devices. Press play button on headphones. iPhone starts playing through headphones at full volume which is totally destroying my ears!
   
   

The general thing is Spotify on my Mac is always on full volume since I controll volume there with the Macs output volume. Mapping this always full volume to an iPhone doesn't make sense to me and gave me a lot of surprised and angry moments lately.

I hope I am not the only one having that issue.