I would like to suggest that volume control from phones is always priority.
What I mean by that is I would like that volume control is always working even when the phone is locked or I am doing something else on the phone. Now I have to open the Rose app.
Could you make this an option in the settings?
Also what could work is that volume control from the Rose is “slave”. So when nothing else is playing on the phone then the Rose volume control is working. When something else is playing on the phone this becomes “master” an d volume control will work for this app and Rose becomes slave and you need to open the app again like it is now.
Best regards,
Merijn