The light button. Short press to turn on in ”deep sleep“ mode. Press and hold until the module vibrates to turn on in ”observation“ mode. Press and hold again to turn off ”observation“ mode.
Press three times to lock all buttons if baby is playing with it.
Sound button works the same way as the light button.
Volume up and volume down buttons.
Lock on/off button by pressing and holding both volume switches until the module vibrates twice.