Go to your app's dashboard, then tap the Siren tile. This is located under the Camera(s) section. You will be able to choose from a list what sound the Siren should play. For example, if the Outdoor Camera detects a person on your garden, you can play the sound of a barking dog to simulate a presence at home.
You can make it sound loud, with all of the other sirens of the house, from the "Sound all" button, which can be accessed by tapping the "Home Alarm" button.
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