Try unplugging the Arc and Sub from power for a couple of minutes and reboot your router and phone.

I have factory reset the sub and arc about 30 times at this point.

Make sure WiFi is enabled on both the Arc and Sub in the Sonos app.

Are you able to temporarily wire the Arc or Sub directly to the router? Does this make any difference?

I attached the an ethernet cable to the ARC and had the sub connect to wifi.

When I do this the sub does not connect to the system until I unplug the ethernet cable from the ARC.

So I let the sub connect to the wifi and system prior to attaching the ethernet cable to the ARC for the last step in pairing the two… which worked wonders the first time.

Then my roommate unplugged the ethernet cable and I’ve attempted to repeat this process with no success.

I am having this same issue when attempting to add the sub to my beam. I am able to connect the sub to my “play one” but as soon as I move it to my beam I’m stuck on the “Adding Sub Mini. This may take a moment...” screen. The loading bar is paused at 100%. I’ve reset and restarted everything multiple times.

What happens if you temporarily wire the Beam to the LAN, if practicable, and then try adding the Sub-Mini to it?

@CooperTru,

If it’s not practical to cable the Beam, then perhaps wire the standalone Play:1 to the LAN/Router instead, but then go onto reboot your devices before trying to bond the Sub-Mini to the Beam.

I unfortunately won’t be able to give that a try. My apartment is wifi only, with no router access.

Very (very) occasionally, a router make/model ‘maybe’ incompatible with Sonos HT main products ‘proxying’ the IP addresses for its surrounds, I’m thinking that could ‘possibly’ be the situation in your case. If you cannot access the router to check a few things, then you may not be able to easily resolve the matter.

In which case one potential solution might be a ‘travel router’, which gives you the ability to log in to the apartment’s Wi-Fi, yet create a separate LAN/Wi-Fi that you have access to / control over. 

I’m not sure how this thread is marked “answered” with the solution provided. This is not an option for folks living in a large city apartment community. We can’t simply log into our community WiFi and create our own network. I’m not trying to be rude but these are not solutions.

I’m dealing with the same issue as OP and I cannot get the sub to connect. I’ve done everything and this is simply unacceptable for the value of this product. I’ve loved Sonos up until now. Every device connects except the sub. Why? Why is the sub the problem? How has there not been a practical solution to this? 
 

We shouldn’t have to jump through these hoops to troubleshoot. I’ve factory reset my sub 20 times at this point and even tried connecting with my iPad this time. ChatGPT doesn’t even know. 
 

If someone can point me to a thread with an actual solution it would be very much appreciated!

A Travel Router is designed to deal with this situation. If you don’t want to incorporate a Travel Router, you’ll need to have the apartment complex network security person make a custom configuration for your apartment. I’m sure that this will not be done. If you use a Travel Router you do not need to deal with the apartment network security.