GeoVolume

Keep volume down based on time or geofence

Have your device's volume turned all the way down based on geofence, or time. Once time is over, or you are away from the geofence the volume levels are restored. You can combine these two factors. In that case, you can be away from your initial geofence, and the volume gets restored, and turned down again once you are within the geofence. If you never leave, then the volume gets restored when time is up.

You don't have to stop the app fro controlling the volume, if you plan at any time to use your headphones. The app can work along and once you unplug your headphones, it knows it's time to keep the volume control once again. Even if your device is turned off, and turned back on, the service will continue as if the device has never been rebooted.