Another vote for nuvos new 7" onwall keypad. It IS NOT WIRELESS. So your client should be ok with that.. then you can run any app you want.. be it nuvo or sonos..

I understand we doesn't want "wireless" but why bother looking for other solutions that may work. It just cost you more time, etc. Nuvo\Sonos you are in and out and they still will have a hardwired solution and those nuvo 7" panels are crazy cheap !!!!