Spectrum Arris TR4400 and RAC2V1A compatibility
This router has a known issue that prevents it from working with Sonos. The solution below will ensure that it will work with Sonos.
Sonos products will not show up in the Devices Available menu in the Spotify app.
Set up your Sonos system in a wired setup and use the Spotify app on a computer that is wired to your router.