There is a tiny little knob on the back of the monitor (numbers 1-5) But the manual says not to turn it below 2 or above 4, if your still getting false alarms in this range then you need to contact the company. Oh and if you want it to be more sensitive (i.e. pick up movement further from the pad) then turn it up (I believe the default setting in package was 2.5 or 3)
Re: Angelcare: How to change sensitivity?