The auto night vision of our baby monitor will switch automatically between day and night vision modes when it detects the change of the light in the room, and you can hear a click sound when it switches, it will switch to day vision mode when there's bright light it detects, and it will switches to night vision when the hand blocks the light and camera can't detect the light. That's the reason why you keep hearing the click sound when someone keeps waving hands closely in front of the camera. It's a normal phenomenon for every baby camera monitor with auto night vision. Our baby monitor with the camera with a 2.4GHz FHSS wireless connection ensures a secure and private live stream that is only for you. 100% Privacy guaranteed.