Reply To: Why my iSmartSafe wireless siren does not sound? Best DIY Home Security Systems from iSmartSafe › Forums › Getting iSmartSafe › Why my iSmartSafe wireless siren does not sound? › Reply To: Why my iSmartSafe wireless siren does not sound? September 5, 2016 at 5:30 pm #4856 ismartsafeKeymaster during setup, you can choose siren type “B” or “A”. if your siren does not work, try to change to type “B”.