You can sound the Siren manually from your application. Open the action menu at the top right corner of the screen, then use the speaker button in the "Sound - Siren" section. You will be able to choose from a list what sound the Siren should play. You can make it sound loud or play a sound effect. 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.