Level 1

9 points

21.5'' iMac - Screen Noise

I just bought and received a new 21.5'' iMac and love it but the screen is making a high pitched noise, similar to a dog whistle. It's that sound that isn't loud but pierces through your brain. And the brighter the backlight is, the louder is gets.

What do you guys think? I love this machine but I don't think it should be doing this and it bothers the heck out of me. Maybe a call to Apple is in order?

iMac 21.5'', Mac OS X (10.6.1)

Posted on Oct 24, 2009 6:59 AM

467 replies

Humis

Level 1

0 points

Nov 8, 2009 12:48 AM in response to Zeta9

This is exactly what I was experiencing with my 21.5" (9400M). I will receive a first replacement iMac at Tuesday, so let's wait if it has the same fault.

Nov 8, 2009 1:43 AM in response to Humis

How did you get your replacement? What's the best thing for me to do: call Apple Care, or go to an Apple Store? I want my replacement as quickly as possible.

Humis

Level 1

0 points

Nov 8, 2009 5:13 AM in response to Reuben Feffer

I'm not sure about that. I ordered mine straight from Apple Store, so that's where I called to.

Nov 8, 2009 1:15 PM in response to steve_lux

Reply on the screen electrical buzz issue when lowering the brightness.
*********************************************************************
I solved the buzzing problem with smcFanControl.
With folowing settings: (all fan speeds 1/3 up)
*OOD 1333
*HDD 1467
*CPU 1253

So I realy think the electrical buzz is an heating issue.
I hope Apple will tweak their fanspeed (or threshold) settings in a software/firmware upgrade.
But this works for now and it's still 10 times less noisy then my HP ProBook notebook. 😉

Kind regards NotoriousT

Nov 9, 2009 1:43 AM in response to NotoriousT

Really? That's great news.

But are we hearing the same thing? You're talking about an electrical buzz. What I hear is a REALLY high pitched whistle sound; a kind of dog whistle sound with a definite pitch.

So how can a high pitched whistle that changes as you change the Brightness of the Display, be related to smcFanControl? What have they got in common?

Nov 9, 2009 5:34 AM in response to Reuben Feffer

Electrical buzz and high pitched whistle sound.

These seem to be 2 non related issues on the new iMac's.
I've solved the electrical buzz sound not the high pitched whistle sound.
The electrical buzz sound seems to be heat related, and it only hanpens when the system has been runnen for a couple of hours.

Sorry, I don't have the high piched sound on my system.

Homee313

Level 1

0 points

Nov 9, 2009 6:04 AM in response to NotoriousT

I had a conversation with an Apple employee from the second-level support who advised me to send my iMac to Apple in Cork / Ireland.

They want to examine the machine.
As soon as it gets there, they will send out an new one.

I wonder if the high pitched noise will also be on the new one.

My first machine was built in the 40th calendar week.

I will report any further progress.

Best regards.

xnay

Level 1

0 points

Nov 9, 2009 1:00 PM in response to xnay

Today I got my second iMac and there is still this noise, but this time it's really quiet and I can only hear it when it's quiet in the room and when I'm really trying to hear it. 😉 (I think some people like my mom never hear it.) So it's not distrubing this time like it was at my first iMac. I'm glad that I can keep this one. 🙂 There also aren't any other failures.
Both iMacs were produced in week 39.

Message was edited by: xnay

Nov 9, 2009 1:20 PM in response to xnay

Xnay, you've confused me 🙂

See, my iMac has this noise, but like your replacement iMac, mine is really quiet. I mean, in terms of decibels it's whisper quiet. I can only hear it when the iMac is the only thing turned on, in a completely quiet room. But it definitely whistles.

So maybe I'm lucky? Maybe the noise could be much louder, much worse?

Now I'm afraid to send back my Week 45 iMac for a replacement, because the second iMac I get could be much worse!

xnay

Level 1

0 points

Nov 9, 2009 1:30 PM in response to Reuben Feffer

My first iMac was really bad, I could even hear it when watching TV or listening to music. It wasn't THAT loud, but because it was such a high frequent noise it was even disturbing when watching a movie on the iMac.

I think I'm glad with my new one, it doesn't bother me because it's so quiet now. Like I told I can hardly hear it. So for me I think there's no reason for sending this one back (except it gets louder in the next couple of days).
But if it disturbs you, then send it back.

VeL1303

Level 1

13 points

Nov 9, 2009 1:45 PM in response to derbyStar16

10.6.2 is out. fix?

Graphics fixes provided for:

an issue when connecting monitors to DVI and Mini DisplayPort adapters
an issue in which the brightness setting may not be remembered on restart
addresses functionality with specific display models
general reliability and performance improvements when using some applications

iSkid

Level 1

5 points

Nov 9, 2009 2:08 PM in response to VeL1303

10.6.2 out. What about screen noise?

iSkid

Level 1

5 points

Nov 9, 2009 2:45 PM in response to iSkid

10.6.2: Screen noise NOT FIXED!! 😟

xnay

Level 1

0 points

Nov 9, 2009 2:48 PM in response to iSkid

This is a hardware problem, no software update could fix something like that.

Nov 9, 2009 4:07 PM in response to iSkid

Same here. Installed 10.6.2, but the whistle is still there.

It seems like this problem can't be fixed via software. I guess anyone (like me) that's bothered by their whistle should be demanding a replacement from Apple.

I still wonder, though, do all the new 21.5" iMacs whistle? Maybe they do, at various volumes. Some whistle loudly, some whistle whisper quiet. But they all whistle.

Message was edited by: Reuben Feffer

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21.5'' iMac - Screen Noise