Best answer by Airgetlam
But let me work through this yet another time. Sometimes things jump to mind as I'm typing.
Your current setup is a Mac, connected to a router with an ethernet cable. You also have an NAS drive of some type, also connected to your router with an ethernet cable. And you have a BOOST, connected to your router with an ethernet cable.
Your music is stored on the Mac, rather than on the NAS.
Is that all correct?
If so, there's a few things I would want to know.
1) why is the music on the Mac, rather than on the NAS? Wouldn't it make more sense to have it there?
2) what kind of router do you have?
3) what frequency is your router using for wifi, is it 2.4Ghz and/or 5Ghz?
4) do you normally have your speakers connected via the wired method (SonosNet) or the wifi (connected to your wifi SSID) method?
5) If your iPhone connects properly, does it show all the rooms, and it's just the Mac that's failing?
6) What version of the controller are you using on the Mac, and on the iPhone?