Need some more information. Where is the noise coming from? You have a couple of places to look for. The air handler which is the unit inside your house, the air return in your duct work  (usually where your filter goes) and the condensing unit outside your home. Could be a dirty filter causing a vacuum … Read more

I have the same problem with the air conditioner , sound comes from right back wheel

Could be spam, maybe thats the noise! 

Oops there I go time traveling again.