Probably, all you would need to do is put all three on the same channel as long as the other Sonos restrictions are being met.

I don’t know Meraki but I have Ubiquity APs and dialing back their capabilities to meet the Sonos restrictions just didn’t make sense to me so I moved to Boost mode with several Sonos wired and reset my APs to leave a channel clear for my Sonos.

Thanks Stanley, How many Ubiquity AP’s do you have in the house?  If you only have 2 I can see where it would be easy to reserve a channel for SonosNet.

The number of 2.4 GHz APs here has varied from 1 to 3 over the years, today I’m down to just one for my 2.4 GHz use, connecting to an older printer.

If you don’t reserve a channel for Sonos you’ll be competing between the AP and the SonosNet mesh for bandwidth. If you could put your most distant and lowest traffic AP on the SonosNet channel you’d have the lowest level of conflict.

With only 3 non-conflicting channels 2.4 GHZ has never really worked well for multi-AP setups unless you can lay them out in a straight line to keep the interference down. Maybe if you fool with the power levels you can get something working using just two channels?

https://documentation.meraki.com/MR/WiFi_Basics_and_Best_Practices/Channel_Planning_Best_Practices

Don’t forget, having all APs on the same channel is a Sonos requirement for Standard Mode (WiFI) use, you can only put your APs on different channels in Boost Mode. So in Boost you at lest get to use at least two AP channels.

Ok thanks. I’m still scratching my head that Sonos advocates for multiple AP’s on the same channel.. completely against WiFi best practices. I’ll investigate enabling Boost mode

I think what you are calling Boost mode is the same as SonosNet correct? Having one speaker wired? That’s how I am running now. I’m not interested in adding the Boost hardware AP from Sonos.

If I have 3 wired speakers and the rest unwired, will each of the unwired have to associate with the same wired speaker, or whichever wired speaker Is closest?

For optimal group performance Sonos units communicate directly peer-to-peer, even in WiFi mode. This can’t happen if units are tuned to APs on different channels.

Thanks ratty, I’m still trying to optimize my Sonos network, tweaking STP now, you had given me a note a year ago about paying attention to 802.1D and 802.1W.  My Meraki switch runs RSTP, but I can manually disable RSTP per port, so I am doing that for all ports wired to Sonos devices and will see how that reacts.  Also to note I have set the bridge priority of the Meraki switch to 4096.

You should only ever have one Sonos device wired to network, either the Boost or one of the speakers or other devices (Amp, Port, etc.)   That single device will provide internet to the entire system over the SonosNet mesh.   Having multiple Sonos devices wired to network WILL CAUSE PROBLEMS!

Each Sonos device will still get a unique IP and will be visible as unique devices on your network. 

P.S.  I have 8 Sonos devices in my home, with a single one wired to my network.  I also have an Eero Pro mesh system in my home with multiple access points.  Everything is setup with default/vanilla configuration.  Everything works great and my Sonos system hasn’t had a “drop” in the year since I’ve set it up.

This is not correct based on info I have received from other users.. I have a large house and some speakers can’t reach the others via wireless, so I need more than one device wired.

Kindly don’t confuse the situation with such unfounded generalisations. The OP appears to be well aware of the need for infrastructure equipment to support STP (actively or passively) when wiring multiple Sonos devices.

The general advice is in fact to wire as many Sonos units as is convenient. 

There are well documented cases of broadcast storms being caused by having multiple Sonos devices wired simultaneously.  Just offering a possible alternative.

And a network with correctly configured STP eliminates these storms, no matter how many wired Sonos devices you have. 

If the three Meraki Access points are each operating on the non-overlapping 2.4ghz channels 1, 6 and 11 then it’s apparent SonosNet running on one of those channels 'may' conflict with one of the Access points on the same channel. I would therefore maybe consider wiring those sonos devices that are in close proximity to the one Access point operating on the same channel, assuming it is practicable to do that.

Alternative options are fine. Bald, un-nuanced statements of the type bolded above could confuse.

So this is what I have found so far. Disabling RSTP on the Meraki switch port apparently disables ALL STP and caused a storm with the two Sonos being wired.  This means the only support Meraki has for 802.1D is with how it is inherently compatible with 802.1W (RSTP), I am waiting for Meraki support to confirm this. In the meantime, I turned RSTP back on globally, and for now things are acting as desired.  The speakers closest to the wired device #1 are communicating with it, and the others closest to wired device #2 are communicating with it.  I have also lowered the power setting on my Meraki AP that is on the same channel as SonosNet and it is already the farthest away from all Sonos devices.  I have a new Sonos Beam arriving this week and may decide to wire it also, but will see how things work after it gets here.

Just a thought, you have 3 APs, do you need 2.4GHz on all 3? Keep the 5GHz radio enabled on all 3, but maybe your home would get coverage with just 2 running 2.4. Use SonosNet on the spare 2.4 channel. 

I can test that but I do have a couple of smart home devices on 2.4 that are closest to the AP with the competing channel, but it’s possible they could work fine on another one.

If all the Sonos connect to Ethernet in the same area could you add a switch that works with Sonos and wire them all to it and then the new switch to your Meraki switch?

Just what the Sonos mesh will look like is beyond my skills, in general the mesh tries to configure to provide the best connections between nodes. Some good discussions on this in the past here if you can dig them up.