I have 3 Nest Minis. If I ask a device by voice to change its own volume, it works. When I make a voice request to Nest1 (named Kitchen) to change the volume on Nest2 (named Room) it completes correctly. When I ask Nest2 (Room) to change the volume of Nest1 (Kitchen) it replies:
“Sorry, I can't control the volume on groups of speakers. Set the volume for each device separately or use the Google Home app.”
- I don't have any speaker groups created.
- My order is being precise and I am pronouncing the specific name of Nest1 (Kitchen) that must have the volume changed, yet it insists as if the name “Kitchen” was the name of a group.
- Through the Google Home app I can change the volume. I can also switch by tapping the sides of the device.
Try rebooting the Mini and if that doesn't help do a full factory reset. Factory reset Google Nest or Home speakers or displays - Google Nest Help.
The Mini may be mistaking your request to set the volume for another device that is unable to be adjusted. A possible solution may be to ask "Hey Google, change the volume to 5/ Hey Google make it louder/" while the media is playing.
I'm jumping in to ensure everything is good here. Have you seen petergroft response? Have you tried the given troubleshooting steps? How was it? By the way, when did your issue begin? Were there any recent changes made? Was it working great before?
In addition to his steps, It would help a lot if you could do a sequential reboot:
Let us know how it goes.