Hi @Plugs78. Shared Users do not have access to change the settings on devices that they aren’t the owner of. You would either need to adjust the volume on your end, or she would need to be signed into your Ring account to have access to the settings on the Chime.
I searched our Feature Request board and found this request, where other neighbors have made the suggestion to have multiple owners. Feel free to add your feedback and vote on that post, as we use the Feature Request board to gather and share new ideas with our teams here.