Best answer by Ryan S
We don’t have any announced plans regarding adding YouTube as an official service for Sonos. We’ll let everyone know if that changes in the future. That said, there are some ways to get the audio from your videos playing on your Sonos speakers. Take a look here:
Line-In
A great way to get any audio into Sonos that isn’t available through our software is to use the line-in on a Sonos PLAY:5, Connect, or Connect:Amp. Using the line-in, you are able to bring any audio content from a device with an audio output to play across your entire Sonos system. The line-in can be played from the player it’s connected to to any combination of players in your home.
Taking the audio signal from a streaming video and playing it through Line-In will introduce a latency of around 70ms. In most cases this isn’t noticeable, however, you may experience lip sync issues if you’re watching critically. If you’re looking for a speaker to pair your audio and video with, you may want to take a look at the Playbase or Playbar. These use optical audio connections which give a higher quality and lower latency.
Smart TV to Sonos Home Theater
This is personally my favorite way. If you have a smart TV or something connected to your TV that can receive a YouTube signal, you can even have a Playbase or Playbar connected to that TV playing YouTube on Sonos. The audio from the Playbase or PLAYBAR can also be grouped with other players to send that audio around the house.
This way sounds great. You’ll be able to see the video on a large screen and hear the audio coming from the same place, the way it’s intended.
Airplay 2
Now available, we’ve introduced Airplay 2 to Sonos players. Using AirPlay 2 you can send the audio from your iOS device to a compatible Sonos player (Sonos One, Beam, Play:5 gen2, Playbase, or Sonos Amp) and once that audio is into the Sonos system, you can group that player with any other Sonos devices to play your audio in all the rooms you want. You can find the full details on Airplay 2 with Sonos here.
AirPlay 2 will allow you to send most audio content being played on your iOS device on Sonos; that includes videos, games, podcasts, and music.
Try out Google Play Music
It’s not YouTube support, but if you have a YouTube Red account, you likely have access to Google Play Music as well. This is an official music streaming service on Sonos and has quite the large selection of music of over 35 million songs. You can also use an Android device to send the audio on your Google Play Music app directly to Sonos players.
Unofficial Solutions
There are some other great ways to get YouTube audio playing on Sonos, though we don’t have any specifically to recommend. You can find some good suggestions and ways to go hidden in this thread, so feel free to peruse the comments.
We recommend keeping an eye on this thread for further updates regarding this feature request. As soon as there’s anything new to share, you’ll be among the first to know here.