- Joined
- Sep 23, 2006
- Messages
- 893
- Reaction score
- 20
- Points
- 18
- Location
- Las Vegas, NV USA
- Your Mac's Specs
- iMac, and Macbook Pro
My wife's new 27" iMac was producing a noticeable and annoying low frequency humming sound. At first I thought it was coming from the screen, so I shut that down. The hum persisted. Then I put the iMac to sleep. The hum went away. It came back as soon as the iMac woke up. I had visions of hauling it down to the store for a genius bar appointment, etc. Then I turned the iMac around and put my ear to the back of the case to try to isolate the area where the hum was originating. Imagine my surprise when I didn't hear any hum at all. At first I was confused by that. Then I gently picked up the iMac, lifting it off the counter top on which it was sitting. The hum immediately ceased. The hum came back as soon as I set the iMac back down. So it wasn't an electrical hum at all, it was a hum produced mechanically by vibration propagating from the iMac to the glass counter top. The glass was humming. I put fairly heavy felt pads on the bottom of the iMac stand, and the hum is virtually gone. It's no problem any more. And, I'm sure that a more sophisticated vibration dampening solution would eliminate the hum altogether. Just wanted to share the information.