I have exactly the same requirement to make the grouping persistent after reboots. I’m trying to recreate a whole home audio distribution to 6 zones and need to group a Wiim mini in the kitchen zone to the Wiim mini connected to the kitchen zone amp just so I can use a Wiim remote control to adjust the volume and skip tracks….which is the way my old Systemline 4.4 system worked.
Just to go into a bit more detail, and I’d be happy for anyone to suggest a better way to do things, the planned setup is 6 WiiM’s connected to 6 zone amp all in a cupboard in the lounge (which is where all the speakers cables come back to) but I want to control a zones volume via a physical remote control from the zone I’m physically listening in…so I was planning to put another Wiim+remote in each of the zones and group back to the appropriate Wiim connected to the zones amp. The theory being that adjusting the volume on Wiim in the kitchen will adjust the volume on the grouped Wiim connected to the amp.
I’d appreciate any alternative way to enable me to adjust volume from a physical remote within the zone. Phones are just not an option as if I start music and leave the room then how does the next person who comes intop the room adjust the volume when they won't have access to my phone.
Final thought…I’d love a Wiim remote that could control a Wiim via wifi, which would solve all the above problems.