No speakers found

The desktop app’s Rooms says:

The network was asked for Sonos speakers and returned none.

It may also say “No speaker can be reached on this network”. The first-run tour says No speaker answered, and the extension says “No speaker answered. Check they are switched on, and on the same network as the companion.”

Cause

The app finds speakers by asking the whole network who is in, and waiting for replies. That goes wrong when:

• the speakers are off, or on another network (a guest Wi-Fi, a separate VLAN) from the computer running the app;
• macOS has not been allowed to let the app find devices on your local network;
• a firewall or VPN on this computer drops the question or the replies;
• the router does not pass the question on, as some mesh systems and most networks split into subnets do not.

If you, or someone in your house, turned off UPnP in the Sonos app, speakers may not be found either. It is on by default.

Fix

1. Check the speakers play from the Sonos app, and that the computer is on the same network as they are: the same Wi-Fi name, not the guest one.

2. On a Mac, allow the local network. On macOS 15 and later, if you were asked whether Thaumic Cast may find devices on your local network and said no, turn it on in System Settings › Privacy & Security › Local Network.

3. Pause any VPN, and let Thaumic Cast through the firewall: Firewall and ports.

4. Ask again. In the desktop app, select Ask again in Rooms.

5. Still nothing? Add a speaker by its IP address. In the first-run tour, select Enter an IP address instead; afterwards, use Add a speaker by IP address in the app’s Settings. Your router’s list of connected devices shows each speaker’s address.

Adding by IP address

One speaker is enough: the app asks it for the rest of your Sonos system. An added speaker stays on the list, under Added by IP address, until you remove it.

What adding by IP address can say

• “Nothing answered at that address.” The speaker is off, or that is not its address.
• “Something answered at that address, and it was not a Sonos speaker.” That address belongs to another device.
• “That is not an address a Sonos speaker can have.” A typo: they look like 192.168.1.100.

Check UPnP

If none of that helps, check UPnP is on in the Sonos app: UPnP is off in the Sonos app.

Thaumic Cast Server

The server finds speakers the same way. In Docker, it needs host networking; on another subnet, it needs mDNS passed between the subnets, or the speakers added by IP address. See Run Thaumic Cast Server.

Verify

Rooms lists your rooms, and the extension lists them too when you open it.