Why does my Sonos Era 100 keep needing setting up again?

The short answer

Usually fixed by getting phone and speakers onto one network name. Repeated re-pairing nearly always means the gadget is losing its place on the network, not that it is faulty.

What's happening underneath

Newer dual-band Sonos radio that still has to sit on the same network as every other speaker and your phone. Splitting speakers from phones needs discovery traffic forwarded between the two networks. Most home routers cannot do it.

Source: Manufacturer documentation

Try these, in this order

• • Put every Sonos speaker and your phone on one Wi-Fi name — main network, never guest.
• • Turn off 'client isolation' or 'AP isolation' on the router.
• • Unplug any plug-in extender and retest.
• • Wire one speaker to the router; the rest of the system usually steadies with it.
• • Check the signal where the gadget actually lives, not where you're standing.
• • Move the router off the floor and out of any cupboard before buying anything.
• • Put the gadget and your phone on the same Wi-Fi name.

Setting it up again properly

• • Stand next to your router while you set it up, then move the gadget to where it lives.
• • Put your phone on the 2.4 GHz network name for the setup, or use one name for both bands so the phone can follow.
• • If your router splits bands into two names, turn the 5 GHz one off for five minutes rather than fighting it.
• • Turn mobile data off on your phone during setup — some apps quietly use it and never find the gadget.

When it's worth spending money

Only after the network-name and isolation checks. A cable to one speaker is cheaper than any new kit.