Just checking - are you setting the sub up via the Arc settings, using “Connect Sub” and following the instructions?

Hi, yes, I am, all sounds so easy, it asks if I want to add the sub to the Arc which obvs I say yes, but then nothing, it is added though because when I add a new product it says do I want to add a second sub so it knows one is there 

When you play some bass heavy music, like dance music, are you able to feel the cone of the sub moving when you put your hand on it…?

No, Sub is definitely not working, App says it’s not connected and WiFi says it’s offline, I’ve seen so much about fixing IP addresses, Sonos support said it was an error with the router, Vodafone says it’s not the router, but I just don’t know what to believe, don’t want to take the system back because I’ve heard it working in store and it’s spectacular 

I’m sure it’s fixable and that some learned people will be along to help on here, now the facts have been established. I’ll think overnight…

Try powering down Arc, Sub and your router. Leave them off for a minute or so, then restart the router. When it’s fully restarted and wifi is running, start the Arc, then the Sub. 

If the full restart above works then you might want to set static/reserved addresses. Usually pretty easy from the router's DHCP settings page.

Thanks all for you replies, tried multiple restarts, tried factory resets on arc and sub, tried deleting and reloading the App, it finds the arc, pairs the arc, arc starts working ok, it finds the sub, pairs the sub, but nothing, app says sub not connected and WiFi says device offline

So an update, I’ve just paired 2 ERA300’s, works perfectly, but still no Sub, someone tell me I have a faulty Sub so I can get some sleep tonight

You have a faulty Sub (maybe). In the morning, try speaking with Sonos support. 

Is it a new Sub that has never been working in your system before? 

Does the Vodafone router have any settings around uPnP/IGMP ? 

The reason that setup appears to work is that it uses Bluetooth LE to do the initial setup. However it sounds like the Sub never actually then comes online with the WiFi. 

Is the Arc connected via ethernet? Does the app say that the Arc WiFi is on? 

Hi, I’m so sorry but I really don’t know what any of that means, everything is brand new, less than a week old, I bought an Arc bar, sub gen 3 and 2 ERA300’s, I now discover that the sub will only work with the 300’s and the 300’s won’t work with the Arc when watching TV, only through Sonos Radio, the Arc is connected to the main WIFI, the sub says offline, I’m afraid my Sonos dream is over and it’s all being returned tomorrow, the experience is ruined, shame because sounds incredible but I’m so far out of my depth with something that should be so easy

Arc is not connected by Ethernet and yes it says WiFi is enabled, the Arc is the only thing actually connected to the network, neither Vodafone (my provider) or Sonos support are helping at all 

Last update from as I’m sure you’re bored of me, so when I set up the sub, it asks do I want to add to arc or 300, when I select arc it doesn’t work, when I select 300, all works perfectly including sub - is this normal, can’t see how it would be but I’d really like some advice, thank you all so much

Not bored… understand the frustration as it should just work. Unfortunately the new app is less than reliable at the moment which is wrecking many peoples experience on Sonos. 

So, if you can pair the sub to the 300’s does that mean all 4 Sonos products are at least showing in the app? If so, from the app, click on the settings cog on the top right, and a section saying ‘Your system’ should appear. Then to the right of that you should see ‘Manage’. Click manage and the first item in the list should be ‘About Your System’. Click that. 

You should then get a list of all components, which should give a version, something like 16.3.1 with a build ID. Check that it is the same for the Arc, Sub and 300’s. 

IF you go back to the previous screen you can go into each component and check the Wifi signal strength too. 

Thank you Ian, all 4 components are on the WiFi and strong connection, about your system only shows Eras and sub - all the same build ID, when I check again, it only shows the Arc but with the same build ID as the rest. On the App it shows the arc as living room and the sub and speakers as living room 2 - should they not be all in the same place as when I set up the system it asks which room to put them in and when I select living room it says one product there which obviously the arc, confused doesn’t come close, I’m now thinking a problem with the arc 

OK, don’t have the 300’s setup as a stereo pair… just have them as two independent speakers in the app, and give them a room name like surround 1 and surround 2… Also make sure the Sub is not part of the 300 setup either, so go into the Living Room stereo pair and remove sub if it’s added and then remove stereo pair. 

Then go into the Arc section and try adding surround then sub… 

Hi Ian, great advice I thought I was getting somewhere, now nothing is connected , only the Arc

Have you restarted each of the Era’s and the Sub? What LED is showing on them? 

Yes, I’ve now restarted everything, inc, the Arc, I have a flashing green light on all components, I’ve done the entire process again and the Eras connect to the Arc ok, but not the Sub, sub still connects to an Era ok, it is a replacement sub so defo not that, thank you for taking the time to message me, it’s actually quite upsetting, Sonos just keep saying it’s a fault with my router, but I just don’t see how, but none of it makes any sense

The sound is really echo ish not at all what I expect 

Maybe you have put the Arc and the surrounds in two “rooms” in the app and “grouped” them? That would result in an echo.

Ok, that makes sense, but when I set it up, it always asks me which room and I always say the same room, app says adding to room, then added ‍♂️

But you are right, they do appear to be in separate rooms but how on earth do I solve that? 

Is this normal if they are in the same room