Instruct: Classify the given review into positive or negative sentiment.
Query: Annoying hum!!!

I can't say if it works well or not since the high pitched hum that this unit generates is so annoying that I immediately removed and returned it. It is not loud just really annoying. Most people seem to not notice it which I find baffling. I am not a bat nor do I have super human hearing and I live in a NYC apartment which means it's plenty noisy already but I could still hear the hum which is almost painful it is so high pitched.