Maybe see this support link and see if the suggestions help…

https://support.sonos.com/en-us/article/reduce-wireless-interference

Changing to a different fixed, non-overlapping 2.4Ghz WiFi channel may help and perhaps setting a channel-width of 20Mhz only - or maybe even try SonosNet (if not using already) and ensuring the wired root device is set well away from the router and operating on a different non-overlapping channel.

Plenty of options there for you to try.

Some further useful reading…

https://support.sonos.com/en-us/article/recommended-settings-for-using-sonos-on-wireless-networks

https://support.sonos.com/en-us/article/choose-between-a-wireless-and-wired-sonos-setup

https://support.sonos.com/en-us/article/switch-sonos-between-a-wireless-and-wired-setup