Working great for months, I add a port and now my speakers are cutting in and out across the board

I think you missed the point here, that being that the new disable Sonosnet doesn't mess with the 5 gHz signal in contrast to the existing disable wifi option that does.

Sonos should still admit they named it poorly and fix that to reflect it turns off the whole radio, not just Wi-Fi. 

I’ve tried to get Sonos to understand this as well, but with no luck.

With ‘Disable SonosNet’ (technically ‘Disable STP’), Sonos appeals to amateurs and semi-profefssionals running an enterprise-grade network at home. Ideally, anyone doing this should have solid networking knowledge, which isn’t always true. As noted earlier, multicast flooding or broadcast storms can happen if network switches aren’t set up properly.

Disable Sonosnet appeals to me and I'm not doing anything fancy.

I simply want to have a couple older Sonos hooked to Ethernet but I don't want my other (older) Sonos puled off my Wi-Fi to Sonosnet, and I don't want to surrender a clear 2.4 gHz channel for a service I don't want or need.

It is a useful option for the fancy network folk too, but I let them make their own arguments.

I don’t understand why you say its named poorly? If you disable WiFi, you use the Ethernet port(s), eg in a high density deployment, Amps stacked in rack etc. This is for advanced installs, and the installers would understand this.

Named poorly because what it actually does is not what the name implies.

You can fix a torn fingernail by chopping off your finger, that may not be what you want even if it is called fix fingernail.

Maybe installers know this label is not accurate and only use the switch properly, but it has made problems for many users that read the misleading name and used it, expecting wifi to be disabled, not the radio turned off.

I might be missing something here, but I just assumed turning off WiFi meant turning the radio off and using ethernet. It says that right on the page for turning wifi off. What am I missing?

That is what it means.  However, not enough people realize that the radios need to be on for a stable connection to surrounds/subs, and they just hook up Ethernet and turn off WiFi, then wonder why their surrounds/subs are misbeahving.

Long time users need to adjust to the new option and labeling.

When the product was introduced in 2005, SONOS did not support WiFI. The SONOS private wireless mesh required at least one unit to be wired to the network. Competition started condemning SONOS for claiming “wireless” when a wired unit was required. Eventually this became such an issue that SONOS enabled direct WiFi connections. While it was a cheap trick for SONOS, it immediately shut down the competitor condemnations. To some extent it was a giggle because the competition had trouble supporting large wireless systems and many competitors ended up licensing SONOS parents.

Many years ago the disable SonosNet option actually disabled the radio, not just the mesh protocol. Initially this was OK and the option was intended to allow installers to reduce WiFi interference when a stack of players was installed in a rack. Also, back then effective WiFi mesh was not widely available for home users. SonosNet was painless (no setup required) and effective — but only for SONOS devices. Back then there were probably just a handful of WiFi devices in the area.

Now, there there can be many dozens of WiFi devices on the network and WiFi hardware has evolved. Hardware in the older SONOS units is fixed. Plus, SONOS uses the 5GHz band for wireless surround speakers. SonosNet only operates in 2.4. Turning OFF the WiFi radios shuts down wireless surround.

Depending on local conditions and hardware, SonosNet can be counterproductive and a second option was added that only disables SonosNet, but allows modern WiFi to continue. Currently manufactured SONOS units use modern WiFi and don’t support SonosNet.

Ah… got it.

Edit: But then how is that mislabeled or named poorly? It does exactly what it says it does. Maybe sonos can add a warning for home theater devices that are using the dedicated low latency wifi, that this could cause problems (Are you sure? Y/N).  Or just not allow it.

The thing is most Sonos users don’t know the difference between ‘Internet’ and ‘WiFi’.

I’m sure there are some that would be nervous about disabling WiFi, as they may think it will shutdown the Internet. 😁