I use YouTube music on iPhone . My nest audio speaker pair is visible in Google Home app , these are also visible from other apps like Spotify , but these are very rarely visible from casting in YouTube music .
I ensure I am on the same ssid ( wifi ).
the speakers can play using voice command by the same YouTube music account , just that many times the device is not visible in YouTube music cast option.
strange that Google home on the same phone shows the speakers and it also shows what is playing on them including the YouTube music icon , but from YouTube music app the speakers don’t appear in casting opiton
this is as of April 2026
