Sonos doesn’t have an article for a speaker dropping out of a group. These steps for the Sonos Era 300 are drawn from its grouping, audio stops or skips and wireless interference articles.

What This Problem Means

A group plays the same audio in more than one room over your home network. Sonos has no article for a speaker dropping out of a group, but its audio and interference articles point to the network: a weak Wi-Fi signal, interference from other electronics or building materials, a slow internet connection, a music service that allows only one stream, or unsupported network devices. For the Era 300 there’s one more point: Sonos’s spatial audio article says grouping it with a product that doesn’t support spatial audio makes the whole group play in stereo.

Common Symptoms

• The Era 300 leaves a group during playback
• Audio stops or skips in the grouped rooms
• The speaker drops out of the room list now and then
• It plays normally on its own
• Dolby Atmos stops when the Era 300 joins a group

Safe Checks You Can Try

1. Group the rooms again

In the Sonos app, Sonos says to “select the Grouping icon in your Now Playing bar”, tick the rooms you want and select Apply. On the Era 300 itself, press and hold Play/Pause to join a room that’s already playing; hold it again to leave. Steps are in Sonos’s group and ungroup rooms article.

2. Restart the Era 300

Unplug the power cord, wait 10 seconds, plug it back in and allow one minute for the Era 300 to start up. That’s the method in Sonos’s reboot article.

3. Restart the router and check your speed

Sonos’s audio stops or skips article says to unplug your router for 30 seconds, then plug it back in. It also says your internet connection needs “at least 5 Mbps”.

4. Check your music service

Sonos says “some music service accounts only allow one stream to play at a time”. If someone else is playing from the same account on another device, that can stop your group.

5. Reduce wireless interference

Sonos’s reduce wireless interference article says to keep Sonos products at least 18 inches (0.5 m) from other electronic devices. It lists cordless or DECT phones, wireless video transmitters or cameras, routers, extenders and access points, wireless audio, baby monitors, wireless set-top boxes, smart home hubs, some monitors and microwaves in use.

6. Look at what’s between the speaker and router

Sonos rates how much building materials block the signal: metal “Very High”, concrete and plaster “High”, water, brick and marble “Medium”, and glass, wood and synthetic materials “Low”. Moving the Era 300 closer to the router helps, and Sonos also suggests changing wireless channels.

7. Remove unsupported network devices

Sonos says extenders, mobile hotspots and LTE routers aren’t supported, so power them off or replace them. If your Sonos system is wired to the router, move the Era 300 nearer the wired product or replace the cable.

When To Contact Support

If the Era 300 still drops out of groups after these steps, contact Sonos and say which steps you’ve already tried. The Sonos Era 300 support page lists Sonos’s help articles for this speaker, and Sonos’s UK contact page has its phone and live chat options.

Last resort: factory reset. Sonos says: “We do not recommend resetting your Sonos product as a troubleshooting step.” If you do reset the Era 300, unplug it, then press and hold the Bluetooth button on the back while you plug it back in. Keep holding until the front light flashes orange and white; it flashes green when the reset is complete. Sonos says a reset removes “registration information, content saved to My Sonos, and content services”, so you add the speaker to your system again afterwards (Sonos’s steps for adding a product). Full steps are in Sonos’s factory reset article.