imac buzzing nouse

[PaddyB]

hi guys i recently bought a 20" imac from the apple refurb online store.

only today i noticed when the screen dims after 5 mins or so the imac will make a buzzing noise. i suspect this may have been an original fault with the imac hence why it was in the refurb store. i am going to call apple in the morning to ask them about this. im just woundering will they reveal the reason
why it was originally on the refurb store? as i suspect it may be for this fault or is this normal?

i only have it since the start of april can u send it back to be looked at??
thanks guys

 

[pjarvi]

Go into the system preferences "Displays" section and try turning the brightness down to see if it is indeed the screen causing the noise. I had a Gateway LCD monitor that would buzz if the brightness went below 80%. It should not make any noise at all, so definitely get Apple to repair it.

 

[anupamgarg]

How much noise should it make?

That's actually something I've been wondering about as well. I bought a 20" iMac from the Refurb store about two weeks ago, and it makes a constant buzzing noise. It is not connected to the display, as it continues even when the display is off (it only turns off when the computer goes completely to sleep). The buzzing is quite minimal, but enough to get annoying after long periods of time.

How much noise should it be making? I tried going to an Apple store to see if it was more noise than normal, but with the amount of noise in an Apple store I couldn't really hear anything.

 

[clyde2801]

Have you tried spraying some Raid on it?

 

[newwbiee]

I first noticed the buzz on the 2nd day after I purchased a brand new iMac 20'. The buzz came on shortly after the machine is up and running (not during start up). The buzz goes away in about 1 minute or a little longer. The buzz became repeatable, so I took my one-week-old iMac back to the Apple store where I made the purchase.

They were cool, I exchanged for another brand new iMac. No buzz on first power on at home, finished setting up/registering, put the machine to sleep. Came back there was the buzz again!

I saw some posts suggesting speakers/screen brightness, I will try and post what I find.

 

[mannix87]

my screensaver has that buzzing noise as well. I think it's trying to mimic an aquarium.

 

[newwbiee]

On my iMac 20', if 'max' is the highest screen brightness, then max/max-1/max-2 (the brightness indicator when you use the two brightness adjustment keys on the key board) are all without the buzz after starting up. Any other brightness level, that is from max-3 all the way to minimum brightness level will produce the buzz with varying pitches. Toggling between max-2/max-3 (while the pitch is still there) consistantly makes the buzz disappear/appear.

Nothing to do with the speaker, as I had speakers off. When the buzz does occur, it goes away after about 1-2 minutes. Once the buzz is gone, no further adjustment on brightness can bring back the buzz.

 

[nikoneko]

Apple care is lame

I took it over there but those deaf genius they say they do not hear anything, apple customer service like any others sucks

 

[iStress]

I assume it's something to do with the heat. I used to get this issue, until I installed SMCFancontrol and now I no longer get the problem. However I get the static "ticking" sound when I turn my iMac's screen off.

What you should try is turn off your iMac (and unplug the power cord), leave it there for about 15-30 minutes, that might help.