As I understand it, WiFi 7 is supposed to be backwards compatible, I don’t think that there is a relationship there. Nor anything to do with frequency in use. Although you don’t mention which speakers you’re dealing with, they all should be able to connect via 2.4Ghz or 5Ghz, given that there is enough signal for them to latch on to. There is a distance difference between the two, and certainly 5Ghz, while faster, is much more easily absorbed by things, of any material (walls, especially, but everything).

What I’m suspecting, as I don’t have any hard data to look at, is a potential IP address issue. What I’d start with is a generic network refresh, which covers a host of potential issues, including the one I’m thinking it might be. 

First, unplug all your Sonos devices from power. If you’re using a BOOST, retire it (if you’re using a BRIDGE, that means S1 and it should also definitely be removed!). Reboot your router, leaving WiFi 7 turned on (although Sonos won’t use it, none of their devices have it built in). Wait a couple of minutes for the router to fully boot up, then plug in your Sonos devices. They should, after running through their boot process, connect to your WiFi signal, assuming you’d previously had told the system what it was.

Once they’re reconnected, make sure they’re up to date, as well, checking in the controller for any firmware and software updates there might be, and applying them all, across the board. 

However, I’m only guessing here…I don’t have access to that critical hard data that is in the Sonos diagnostic. I suspect that the person you spoke to when you called in didn’t quite understand the implications of WiFi 7 either, given how new it really is. You may need to call back in and speak to someone who has a better understanding of the situation you’re confronting.

Thanks Bruce I will try it. I did send diagnostic data to both Sonos techs I spoke with over the past several months. Both told me some version of the Wifi 7 issue and the different frequencies, but I will reboot everything.

It sounds like Sonos needs to provide more training to its tech help.

As WiFi 7 becomes more prevalent in the marketplace, I suspect you’re correct. Right now, I think it’s relatively rare, but increasing in its penetration. 

Make sure the new router hasn't disabled any of the old wifi standards your older Sonos may require.

There is a support document for that, hard to find from this small screen or I'd link it.

​@fridaykr 

I have a Wi-Fi 7 Mesh Network meaning that I have a main router and two satellites spread across my home. Needles to say a single Wi-Fi 7 router will work with Sonos if properly configured.

A Wi-Fi 7 router will typically be Tri-Band meaning it has 2.4Ghz, 5Ghz and a 6Ghz bands. The most important factors for a successful Wi-Fi 7 setup are:

• All bands should have the same SSID and Password
• All Bands should be active
• Do not put Sonos on one band..let the speakers choose their preferred band *
• Band Steering (Smart Connect) should be turned off
• Airtime Fairness should be turned off
• Security should be WPA2/WPA3 Personnel

Below is a link to an article I posted regarding Mesh Network setup mistakes; if yours is such.

 * Sonos will ignore the 6Ghz band

Giant post from the OP and they failed to say what router they are using. Sigh.

We know ASUS have historically had trouble with new models working correctly and breaking Sonos, and we further know their Wifi7 had some new incompatibility with Sonos.

I’m going to guess the OP has an ASUS router.

However, never say never. but…..

I’ve never had problems with Asus routers through 802.11 standards of Wi-Fi 4 (n), Wi-Fi 5 (AC), Wi-Fi 6 (AX) in mesh configuration and now Wi-Fi 7 (BE) also in mesh configuration. 

Admittedly, with Wi-Fi 4 and Wi-Fi 5 for a time I used a Bridge/Boost; but the Asus router was always my hub.  It was with Wi-Fi 5 that I originally ditched the Boost and setup my first AiMesh consisting of three (3) Asus routers. 

I’m currently running Asus Wi-Fi 7 routers in AiMesh as follows: *

• GT-BE98 Pro Quad Band 2.4Ghz, 5Ghz and 6Ghz x 2 (main)
• RT-BE96U x 2 Triband 2.4Ghz, 5Ghz and 6Ghz (satellites)
• Ethernet Backhaul
• Airtime Fairness > Off
• Smart Connect > Off
• Encryption > WPA2/WPA3 Personal
• SSID and Password > Same for All Bands

My Sonos consists of nothing older than a Port, Amp and Sub 3.  Speakers are:

• Arc Ultra x 3 with Era 300 surrounds and Sub 4’s
• Beam 2 with Era 100 surrounds and Sub Mini
• Era 300 stereo pair with Sub 3
• Era 100 stereo pair with Sub Mini
• Fives in stereo pair with Sub 3
• Amp driving Def Tech tower speaker X 2 with Sub 3
• Amp driving Def Tech bookshelf speaker X 2 with Sub Mini
• Move2 in stereo pair
• Roam2 in stereo pair (only when Move2 are off-line)
• Port (not in use)

JMO, but I suspect many users who have older Sonos units are:

• Leaving the Asus router Encryption set to WPA3 which is default. Not recommended as many legacy devices have trouble connecting under WPA3. 

Barring internal/external interference…the user may be incorrectly doing at least one of the following: 

• Separating the Bands with different SSID’s
• Leaving Airtime Fairness On
• Leaving Smart Connect On

One last aspect is that they may be trying to extend the Asus Wi-fi signal using 3rd party extenders and/or routers. I’ll admit that Asus doesn’t play well with others.

So, FWIW there you have it.

* I also have QoS enabled with “Streaming and Video” as priority. However, many say QoS creates a problem with Sonos. From my experience I can’t say that it does. Therefore, I’ll not comment further.

For thought and capture by search engines. 

I replaced/upgraded my AT&T router with an extender to the BGW620-700 (Router) / 4991 (Extender) combination. The replacement process, which of course is already painful with Sonos, was made worse by the lack of backward compatibility in the Sonos product. My Roam moved over fine, but (1) Arc, (1) Sub (Gen 3), (2) Roam (Gen 2), and (2) Amps would not connect. After a lot of searching, I initially used the “Max Compatibility” mode in the AT&T gear, which pushes the system from Wi-Fi 7 back to (apparently) Wi-Fi 6e. At that point, everything worked fine. After re-registering on the network, I attempted to go back to “Max Performance” on the AT&T router, but to no avail. Only the Roam would continue to work. 

Today, I had time to switch the system over to Wired Ethernet. I plugged in one of my Beam devices to my wired network, and, much to my surprise (I had low expectations of this being seemless), the Beam registered on the network, and then very quickly all of the other devices (besides the Roam) joined the private Sonos network this process creates, and began working correctly. The question I had based on the available documentation was whether the Roam would continue to work as expected, and was please to find out that the answer was YES. 

So to everyone having this issue, save yourself a lot of headache and just plug one of your devices into ethernet!  

If deciding to go wired, keep in mind not all Sonos support Sonosnet and will still need wifi.

Also you need a clear wifi channel for the Sonosnet wireless link.

Just an addition to ​@Stanley_4 ’s comment “not all Sonos support Sonosnet and will still need wifi”. Instead of “wifi” I would have said “a network connection” - for example the Arc Ultra does not do Sonosnet, but can be connected by cable; it does not need wifi per se.

My apologies for not being so clear on what devices support Sonosnet, ethernet, etc. This information is easily obtained. 

What is dificult is finding “hey I have XXX router config and Sonos is broken”

With any luck, either Sonos or AT&T (and other router providers) will update firmware to support backward compatiblity better. 

It’s pretty sad that of my entire home full of smart stuff, Sonos are the ONLY devices that did not work on the new router. Cheap Wi-Fi smart plugs, 3 year old ceiling fans, an old HP laptop that I don’t even think does WiFi 5… all work. Not Sonos. 🙄

Sonos certainly ‘exercises’ networks in ways many/most other devices don’t, although as near as I’ve been able to research, within specifications for networks. 

I have 10 Sonos products a combination of old S1 products and new S2 products.  Just moved to a new location and changed ISP.  New modem is Panoramic Gateway Technicolor XB8 (Rev 2.5) from Cox Communications (supports up to 1 Gig).  The old modem was also from Cox but had ability to specifically set band to either 2.4 or 5 Ghz.  I ran everything on the 2.4 band. The new modem utilizes band steering, but Cox says not to use it.  Tried to reinstall all my products and controllers.  Only products hardwired via ethernet will connect.  No wireless capability at all.  The new App now combines both S1 and S2 units, but always defaults to S2.  Spent over 5 hours with Sonos trying to resolve issue.  They said no viable solution except to hard wire all units.  None of my units will register to the new router and my Mac desktop controller for my S1 products will not connect to the new Modem.  My only solution is to either wire my come for ethernet or change products.  Even upgrading everything to S2 does not solve the problem.  Units cannot be updated or registered.  Besides looks like Sonos is a sinking ship so why spend more money.  After 20 years with Sonos products to be left high and dry is unacceptable.   Sonos creates Apps and updates wireless products without user interface or communication with major ISP’s.  What is the advantage of wireless products without wireless capability?  I can’t be the only person to experience this.  BTW the modem from Cox is the exact same model as is used by Xfinity.