I don’t quite understand what you are asking. Are you talking about controlling the volume on your Sonos Arc? What exactly do you want to disable?

So on my app i have 3 rooms the patio and master bedroom have other brands of speakers with the patio set up with an amp and the mb set up with a port my family room has the arc with ceiling  speakers and a sub. I can control all the volumes individually or together on my app. But the problem is when someone  goes to watch tv the remote volume works but if the vol on my phone app is too loud u cant lower the volume enough. U can have it on 0 and theres still sound. When it was set it up originally my app couldn't control the family room i was only able to controlled the volume with  the remote. When im not home its a problem for my family. I hope this makes sense i know theres a way i just cant remember how to change it back

Are you saying that controlling the volume of the Arc with your remote doesn’t match the volume of the Arc in the Sonos app? Is the Arc grouped with the speakers in your other rooms? Do you still experience the same problem if the Arc is ungrouped from the other rooms in the app?

Here’s an article on how to group and ungroup  rooms:

https://support.sonos.com/s/article/3391?language=en_US

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