This product is advertised as having a "light sensor to deactivate sounds at night." But when I gave it to my brother as a gift, he said it would wake him up at two in the morning because the bird calls would still go off. I didn't believe him, so I brought it home with me and the first few nights I didn't notice anything. But one night I stayed up late (with the lights off) and, sure enough, I could hear the Mallard and Morning Dove. I also noticed that the bird call for seven o'clock is broken.
I thought this would be a great gift for a bird watcher like my brother but I was wrong. I only wish I had caught this in time to return it. But as it was a gift, I didn't find out until it was too late.