Sonos constantly dropping out

That eliminates the easy solution to a fairly common problem. 

I'd suggest powering off the Boost and unwiring all other Sonos to go to wifi mode instead of bypassing your wifi (aside from your Roams) for Sonosnet,  and then use the network diagnostics to check individual device's signal strengths.

If you have access to a signal monitor you can look for 2.4 and 5 gHz channels with low utilization and noise and pick the best for your router's wifi.

As this is a recent problem I'd suspect something changed in your RF environment as the easy option. Not so easy would be router updates that tweaked something.

Support can be a aggravation but waiting for issues, submitting diagnostics (more than one isn'tbad) and then a phone call to support is about the last resort if nothing else helps.

Once you have decided that the issue must be [ … ] or cannot be [ … ] you are likely to be blindsided. But you should play the percentages. Network is a high percentage item.

Factory Reset rarely resolves fundamental issues and is generally a waste of time, but it might accidentally, temporarily work through an issue. Note that Factory Reset of SONOS units destroys diagnostic data that would have been useful to SONOS support.

Evidently something showed up in a diagnostic because SONOS support focused on the five far away units. I think that support should have been more specific than you indicated. You could selectively power down these units and keep notes. In addition to a hardware issue with one of these players, there could be a neighbor who added an offensive new device.

Many of the players listed in your profile will ignore SonosNet. If some or all of the distant five use SONOS net, moving BOOST closer to the five might help. As long as another SonosNet device is wired and in range, BOOST does not need to be wired.

I once had an intermittent issue while playing music stored on a NAS drive. It was an ancient drive and old age failure was a possibility, but the very intermittent nature of the issue suggested a network issue, possibly a duplicate IP address …  but I’m too smart for that … right? I finally swallowed my pride and checked all of the addresses … darn!! Several weeks prior I had slightly reconfigured my network and changed all of my reserved addresses accordingly. Unfortunately, I had forgotten about a seldom used little palm sized controller (using a fixed address) hidden in a cabinet. This unit duplicated the IP address of that NAS.

Now I’m joining in on the nightmare myself.  For the last two weeks my music just stops playing.  I unplugged all my Sonos products, my router, my modem and waited 5 mins before plugging everything back up and checked the Sonos app for an update.  Worked for a couple of days then stops playing.  This is really causing problems because I leave the system playing dog calming music to reduce their anxiety when we are gone to work.  Also my bedroom speaker that plays theta waves for sleeping cuts off in the middle of the night.  Really staring to get irritating, and then come to look for solutions only to see everything is being blamed on network issues, yeah because everyone having the same problem has the same internet provider, router/modem connection, etc… The only thing I see that is consistent is we all have Sonos speakers so seems something is up with an update or the app in general.  
 

I will tell you this, I have never had Sonos issues in the past and my router has always been eero. In October eero pushed out the worst firmware update I have ever experienced. It tore my network to shreds. After a month and a half I got fed up and changed my router to a TP Link setup. Sonos has been nearly perfect since that change along with the rest of my network. Something to think about in case you are on eero. 

There are plenty of Sonos Support pages at the link below that can often resolve such issues. So maybe start with those…

https://support.sonos.com/en-us/search?q=Wireless+interference

If no joy from doing some of the simple things mentioned, like changing WiFi bands, channels, or channel-width etc. then maybe go onto submit a Sonos System diagnostic report, shortly after the music/audio stops (if practicable), or at least as soon as the issue is realised. Make a note of the diagnostic reference and go onto contact Sonos customer care Staff via this link below, to see if they can perhaps help you identify the root cause:

https://support.sonos.com/s/contact

Hope you can get the matter resolved. 👍

Sometimes, “free” music services, will dump clients after a time interval because the services don’t want to play for pets. If this is your issue you could use an alarm to restart the service just prior to the average timeout.

Using your local Music Library will remove external issues.

Have had Sonos 1 for at least 5 years, in this time it continually dropped out, the frustration it gave me drove me to tears, in one case it drove me to the bottle shop.

l rectified this situation by purchasing Apple Homepod this rectified the situation so user friendly connected within seconds,no drop outs ,no frustration.

Yes l am still with same internet provider nothing changed.

Sad this remains an issue.  For a 10+ year Sonos client, it seems like there are always issues.  I was a huge Sonos fan.  Great concept, then Sonos 2 was released...app sucks, speakers are no longer supported, and many smaller issues with hours on the phones with Support with no real answers.

My Sonos is one foot from my Eero’s router.  Everything else seems to work fine multiple laptops, tvs, phones, tablets, and anything else connected to the same Eero’s network.   I don’t believe this is a network issue, it’s a Sonos error.  If someone could recommend a better non-Sonos solution, I’m game.

Honestly thinking about using Turtlebox speakers.  At least I can have a portable solution for the same price.

One foot is a pretty close distance for a radio powered device. Have you run an Ethernet cable between the router and the Sonos, and turned off the radio in the Sonos? It’s somewhat likely, being that close, that you’re getting some odd radio signal interference.