That’s a lot of exclamation points!
You have got a couple of things to look at, based on the information provided. The first is the information in the wifi interference FAQ. Remember, however, not all interference comes from devices that are in your network, or alternately are in your home. On two separate occasions (and locations), I’ve had to deal with a failing microwave ‘leaking’ interference, and a new neighbor with a new router location and channel. Fortunately, at least for me, sunspots have not yet been an issue.
Second, there is the possibility of duplicate IP address issues causing interruptions in the data being received by your speakers. The potentially shorter term solution to this is to power down all Sonos devices, and while they’re powered down, reboot the router. Give the router a few minutes to come back up, and plug back in the Sonos.
Of course, any router that has gotten to this state once can do so again, so the longer term solution is to assign reserved IP addresses for all Sonos devices in the router. The instructions on how to do this would be in the router’s manual, each company seems to do it slightly differently, and there is no way to force this in software by Sonos.
However, these two possibilities are only the most likely of the potential issues. If neither of these suggestions work, I would recommend that you submit a system diagnostic within 10 minutes of experiencing this problem, and call Sonos Support to discuss it.
There may be information included in the diagnostic that will help Sonos pinpoint the issue and help you find a solution.
When you speak directly to the phone folks, they have tools at their disposal that will allow them to give you advice specific to your network and Sonos system.