Google Nest Mini and Chromecast not working after getting new router

[Ces]

Router: E5-250MA | I'm using a Pixel 7 to set everything up

I set up a new router at home and I have encountered a million errors while setting up my Nest Mini and Chromecast. Everything worked more or less normally for a day or two, then the system collapsed (devices can't be found any more) and with every reset, I now encounter this error on Google Home. The devices work fine when I use a different router and connection.

At first I thought it was a frequency thing (with the devices not being able to talk to each other due to being on different channels). So I went into the router settings and turned off "5Ghz Prefer", unbundled the two networks and tried using 2.4Ghz and 5Ghz in isolation. No changes.

Throughout all this I tried every combination or reset you can think off: rebooting every piece of equipment, factory resetting both the devices and the router, uninstalling/clearing storage/cache in the Google Home app. Nothing made a difference.

There doesn't seem to be any AP or Client isolation setting on the router. 

 I have tried:

• enabling 2.4Ghz only

• enabling 5Ghz only

• disabling Guest networks

Each time rebooting the router, factory resetting the devices and uninstalling the Home app.

There is no AP Isolation setting that I can see. I have turned off IPv6 and turned on UPnP. Made no difference.

I have also tried renaming the different connections (different SSID), and forgetting old network settings. Made no difference.

I have also found that if I set up a TP-Link range extender (not that I need it, since everything is in the same room, but it mirrors the connection at 2.4Ghz), everything works more or less normally. I can even go back to connecting directly to the main router and control things for a while, until they disappear again randomly.

There has to be something going on with the router, but I think it might be beyond my technical capabilities. I even used a WiFi Analyzer to make sure that when the router is set to 2.4Ghz it's definitely only using 2.4Ghz. But still the devices don't seem to be able to talk to each other that way.

Any suggestions welcome. Thank you!

[Ashmahalahala]

Believe I’ve found the solution, it’s not pretty but it’s working right now.

Untick ‘Prefer 5ghz’ and rename your 2.4 or 5ghz SSIDs to be different names from each other. Do this in the ‘Wi-Fi basic setting’ page and check it’s done in the ‘WLAN Settings’ under Advanced > Wi-Fi. Run all your smart home devices including TVs and Chromecasts etc on the 2.4ghz SSID. Connect your phone to 2.4 and it will work.

Downside - my PS5 is fine on 5ghz, but if you have a gaming PC and want fastest gaming network speeds but to be able to cast as well, you’ll need to swap between your 2.4 and 5ghz SSIDs. This is purely a router problem - it’s unable to marry up communications between devices on its 2.4 and 5ghz networks. I’ve never had this problem on any other Wi-Fi systems, but I know Three is not unique in this problem and this can exist on standalone off-the-shelf routers. Swapping between SSIDs only really matters for devices that you want fastest speeds possible on, but also to be able to communicate with your smart home devices with.

I’ve only just implemented this change and will report back how it goes, but it’s working for now. In summary: Three needs a better router!

[Ashmahalahala]

Can confirm this has worked well.

[Blackwood]

Same here, trying to stream my PC to TV but no dice. Very frustrating.

[Ashmahalahala]

I believe I have found the issue - AP isolation. This is a function that prevents devices on the same network from communicating with each other.

the problem is that this setting is not available to be changed by users and the Three technical support team suggest that I change it or contact the manufacturer… bruh

[Ashmahalahala]

Ces, I’m having the EXACT SAME issues with the same type of devices with the same router model. What’s more, I’m an IT technician… and I still can’t get things to work properly!

For me, I can cast to one of the two Chromecast devices in our house most of the time, and our Nest Mini can the FIRST time, but once another device has requested casting I can’t control the Chromecast anymore. I saw somewhere online about the UPnP setting too, which doesn’t make much difference. I set up WiFi as part of my job and this has been more painful than most things at work, especially for my non-technical partner.

Three: I’m almost certain this is a firmware issue. Please sort it out, we’re getting pretty frustrated now.

[Ces]

Thank you! This makes me feel less alone and less inept! I hope we'll get some sort of update soon.