I have a paired Sonos one setup and the problem is as follows: 

sound source: a Mac connected via Airplay on the same wifi + Sonos app installed  on the mac (if it matters)


Explainer: Sonos plays a video (sound) perfectly. I select a new video, the video starts but Sonos does not play the sound anymore. To solve the problem I have to change output device on the mac to something else, then select the Sonos again and it starts to play perfectly. 

This also happens if I switch applications when e.g. a youtube video ends, I use an other app, i revisit youtube in the browser and i have to do the “switch output device” again. 

I tried with different browsers already. It has been happening since I have 

Curious if it happens with others or what is going on.