Best answer by Airgetlam
On the mobile, which I have handy, you'd go to settings>Room Settings>Living Room>Separate Stereo Pair. Then go back to settings>Room Settings>[Name of speaker you want to change]>Room Name> and select the room name you want, i.e. kitchen, or backspace over what's at the top and put in your own name.
I'd assume it's similarly placed in the desktop controller, but I don't have one on the machine i'm typing on right now.