My hearing is not what it once was...LOL I almost accused my wife of hearing things then my two boys said they also heard the same sound. Once I got close to the unit I then could hear the sound. When I took it to the dealer I still could not hear the sound from the drover seat, bu the service person stated he did hear the sound and even heard a sound when he shut the unit off. They stated the blower motor was bad, I believe this is almost a defect cause I have read about this in other social media sites/forums and with the part being backordered till the end of this month I believe I'm right. Hopefully I'll get mine replaced at least by the end of January bringing of February. I will add that I can now hear the whining sound or what ever sound it's supposed to be.