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?
I bought an iMac 21.5" about a week ago. Everything was going great, until i noticed the high pitched sound that the screen was making. I called Apple, they did everything they could think of from the phone, and then they told me to go to the Apple Store where I bought my Mac. Went there, got the machine replaced, no questions asked. I come home, and i try to find the high pitch sound. It's still there for all the brightnesses except for the last one (the most bright the screen can get). I tell myself that that's fine since I will be using my machine at full brighteness all the time anyways. So for a day or so, while I was in full brighteness the screen wasn't making the slightest noise. Then I did the updates, which also installed the last update of Mac OS X. And here we go again! The noise reappeared in the same form as it manifested itself in my first iMac. Called Apple again, they did everything they could do again. They retrieved as much info as they could from me regarding my issue and they said that they would forward the issue to a team of engineers and give it high priority. They said that they would call me back next week with an update. Changing the iMac again would probably not do much, that's why they advised me not to go and replace my mac again. Now i'm still waiting...
Hope this helps everyone else that is having the same problem.
Also, another interesting thing is that I have installed windows through bootcamp. When i log into windows, when I am at max brightness the high pitch noise is not there. It's only there when I put the brightness to around the middle, and it's very faint when the brightness is at the low end.
Hopefully this means that this is some software problem rather than a hardware problem, and a simple update will be able to fix this.
Lets all hope for the best!
I have a late 2009 21.5" iMac which makes the noise between setting 5 and one under maximum brightness, its inverter hum, it did it on OSX 10.6.1 and still does exactly the same on 10.6.4.
Some of those updates are security fixes, I would update personally to get bug fixes and security ones, the problem has been there for a year, and I doubt you will ever see a software fix for this, as its a hardware issue I believe, its like the noise a dimmer switch makes really.
Some people can here the whine very clearly, generally younger people as their hearing is more sensitive, at my age its not so bad. In other words its there to stay more than likely with this generation of iMacs so don't miss out on updates.
So they called me back today. They told me that their team of engineers found the issue, and it's a faulty wire that has something to do with the screen. The wire can be replaced and the problem will cease. Or at least that's the plan. I am supposed to bring my iMac back to the Apple Store where I bought it, and there the Apple tech guys will take a look at my case number to figure out the parts they need and do the replacing. Hopefully this will fix the problem, and I will be able to enjoy my mac noise free.
Good luck with that, I think its been tried before, but if it works post back. TBH having a new machine taken apart for a problem that should not be there in the first place...well I would not be happy, that's just me though, no new iMac should need work done on it to make it fit for purpose, especially when this issue is a year old almost.
My new iMac has the same problem (bought it yesterday), 10.6.3 the high pitch tone is gone at the latest two 'brightness blocks'
But when I install the update to 10.6.4 the high pitch tone is always there..
I also have the yellow tinge
I can't believe that this issue hasn't bee fixed yet. I bought a 21.5'' iMac when they were first released in October '09 and have been through 5 of them until I found one that didn't whistle when adjusting the backlight.
And all I heard from Apple support was that it was a known issue and engineers were working on it. Well I guess they didn't work too hard.
It's stuff like this that'll make me very leery about buying an iMac in the future. These products are supposed to be the best built computers on the market, hence the price tag.
Its put me off buying another, they upgraded my 21.5 for a 27" that arrived with fluff behind the glass and scratches on the lcd as well as fingerprints, they would not replace it as they said "we cannot guarantee you will get a better one" I could not believe that, I kept my 21.5" as at least the noise it makes in inaudible at the light setting I have, its put through a smart UPS with a sinewave output as well. Not sure I'll be getting another iMac though.
I bought one of the brand new iMacs this week and I've also got the high-pitched noise level in every brightness setting except the lowest under Mac OS X. When I boot Windows via Bootcamp though, I don't hear the sound when the brightness setting is maxed out - sounds like a software issue to me.
