Light, but Voice Activated

Several month ago, I broke a switch in our bathroom. And it was repaired last weekend. My mother told me happily: “This switch is voice activated. It will go off if you say ‘Kai deng’. And it will go out if you say ’Guan deng’.”
But I find out a big problem. When I take the shower. A light in our bathroom often goes out. Why? Because the switch is voice activated, and I am used to listening to the music when taking the shower. So I always say “Kai deng” loudly. It’s always embarrassed me.