Just received, I plugged in by leaving it on the position by default (duet). And then, surprise, my dog runs away from the room and starts to bark non stop until I unplug the device. I tried the 4 positions (duet, ultra, trans and test) but ditto for 4. So, I do not know if it is effective against mice and insects as it is impossible to leave connected because of my dog. So very disappointed in this product. After, it is true that in the description, it is not specified it can be used when you have a dog or a cat, I was placed reliance upon a previous comment, I should have been more suspicious. I also said that even I can hear ultrasounds so for those who sleep in the same room, think about it (personally, I could not sleep on hearing these ultra sounds, even the weaker our position remains audible ears);)
Edit: I finally gave my father who in his basement connected to scare away mice. From what he told me, it's effective, mice are gone, at least for now. He said that in the strongest position, even had him struggling to stay in the room more than 10 minutes.
