Some additional information is needed in order to help, and unfortunately, we don’t have access to any diagnostics. What else can you tell us about your network?

Which particular Cox modem do you have? Does your WiFi signal match the data in the the Sonos Network Requirements FAQ, and the linked FAQ here? Which particular Sonos devices do you have? Are you running the S1 or S2 controller?

You say ‘back to’, does this mean it worked before? Do you know what has changed, and are willing to share that information with us?

Yes it matches requirements and worked just got a new modem but same model. Now will not connect. Spent 2hrs with tech support they couldn’t figure it out. Said I’d have to hardwire it? S2 controller.

i have playbar, speaker 3’s, sub. 

While this is good information, I still would like to know the broadcast data, I.e. what type of WiFi signal (channel, frequencies, security types) are being sent by the router. And I’m assuming the SSID and password haven’t changed, you’re using the same as before?

When you say 3’s, can I assume you mean PLAY:3s? Sonos has never made a 3. 
 

Have you tried, at least temporarily, wiring an Ethernet cable to the PLAYBAR?
 

Yes. Hard wire works wireless does not. 
yes play 3.  I’ve tried both 2.4 and 5 channels. Standard wap 

B/g/n? 
Which broadcast channel are you using? Please, the more details you can add, the better the analysis of why you’re not connecting. 

How far are these devices from your router? Is there a possibility of wifi interference , or the potential of turning off the WiFi / radio in the PLAYBAR?

I’ll work on it today. Thanks for feedback. I also have an old bridge I haven’t had to use in years but will give it a try as well. I’ll update soon. 

I’d stay away from the BRIDGE, it’s both S1 only, and known to have a dodgy power supply occasionally. if you need to go that route, use a BOOST, which replaced the BRIDGE. 
 

I think the BOOST has just been retired from the Sonos sales page, but if needed, you could pick one up from a third party company. I use one for convenience sake. It runs either S1 or S2, is faster, and has a better power supply. It’s also a bunch newer. 

Bridges are, obsolete, common causes of hard to figure out problems, and S1 only.

I’m on Cox but brought my own modem and router to avoid the Cox hardware. I’d suggest running a temporary Ethernet to one of your (non-sub/surround) Sonos to get the system functioning. Once there you can work on it further if you want to go WiFi only.