In general, when using an mesh network like eero, Sonos recommends using their system in ‘wired mode’, where one device, either a BOOST, or a Sonos speaker, is wired directly to the base device of the network. This is due to the fact that many mesh networks function by breaking up your WiFi into multiple subnets, all using the same SSID and password. This breaks the ability for the Sonos devices to communicate amongst themselves, which is key to their function.
It’s not clear from your post how your system is set up. Making sure it is a ‘wired’ system may help your situation.
However, if your system is already set up in that manner, it is always possible that the router’s DHCP table has handed out duplicate IPs to your Sonos device, and potentially other network devices. The easy process to ‘fix’ that issue is to unplug all Sonos devices from power, and while they are unplugged, reboot the router. Once the router comes back up, plug back in the Sonos devices.
For what it’s worth, if that process ‘fixes’ the issue, it would be recommended to read the router’s manual, and assign reserved IP addresses across the board. Any router that has given out bad IP addresses in the past, for whatever reason, can be assumed that it can get back to that state again. Fortunately, setting up reserved IP addresses helps keep that from happening.
edit: I type more slowly than @jgatie ;)
