Volume slider not accessible with Live Viewer permissions

I have users that are only allowed access for live viewing and user input so they can listen and respond to someone at doorbell cameras. However, when they don't have access to the playback panel there is no volume slider available and it seems that their default volume level is at 50%, which is too quiet to hear. We have tried giving them temporary access to the archive so they can adjust the volume to 100%, but when reconnecting to the system it reverts to 50%. Is there a way to adjust the client volume while only having live viewer access?