speaker noise on my 2011 27" iMac

[mrzeigler]

When I wake my iMac, I always hear a soft, muted noise that sounds like wind blowing across a live microphone. It lasts for three or four seconds, and then resurfaces intermittently.

Any suggestions as to the most likely culprit?

 

[mrzeigler]

I finally had time to call AppleCare about this, and the tech suggested it might just be noise from the fans.

Those of you with the 2011, 27" iMacs ... can the fan make a soft, rustling sound similar to wind blowing over a active microphone, or perhaps the rustle of a soft cloth?

 

[shawnathan]

My early 2009 24" iMac has done this ever since I got it. Sort of a soft, feedback sound. It only happens once in a while though, so it never bothered me enough to call Apple Care. I just need to tap a volume key on the keyboard and it goes away, so I don't think it's the fan. Sorry I'm not any help, but if you figure it out, repost.