Hi Guys.
Maybe a little of with this question.
but don’t know any where else to ask it, since I’m just buying my first Pi and primary gonna
try to control Spotify from a Crestron system.
I wonder if it would be possible with your software or if anybody know if it even would be possible to make like a Matrix audio mixer with external inputs on a Pi master unit.
Let say you have a Pi, where you can have multiple audio inputs so you can put in your computer, apple tv, chromecast etc. audio signals, and tell what signal you want to play at what receiving Pi, by telling the “master” which one or ones or all, receivers to play from eg. input 1 (or for stereo 1 and 2). and play it on receiver “1 for living room”, " 3 for Bathroom" and 6 for outside room.
and also be able to set volume for those.
Or maybe if it has power and support for it, use a soundcard with eg. 10 inputs (5 stereo sources) and stream them all on the net. and tell the pi’s in that room you want the sound in, what channel to listen to.
but still think it would be more efficient with being able to say direct what source should go to
what receiver you want.
And why, because i want to have everything in a server room, but wants to be able to listen
to every source there is, even video sources.
For now I’m using a audio processor that have 10 inputs and 6 outputs. 2 channels for stereo in living room, 2 channels for stereo in bedroom, 1 channel mono in kitchen and one channel mono in bathroom.
but for this i need to use signal cables or speaker cables to all room, which could be minimized by a setup with pi, if they can handle all data 
Hope you understand my bad English!