Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Quiet only for deaf people

This machine is really only Quiet if you have hearing problems. Seems like a factory inside, even on the so called sleep mode. My cat is afraid of the noise, in sleep mode. When put on medium or high mode, she leaves the room. It's more like a vacuumcleaner. I really do not understand how people can say that this thing is quiet in sleep mode. Comment this if you want to hear a recording of the background noise on sleep mode :)