IMac, low brightness, sound buzz

Hi, i'm italian mac user, and i bought my imac ( 27" i7 1 Tb HDD 4 Gb Ram) last week, and other user tell me to try to make low brightness in my mac and effectively if i make the brightness to low i feel buzz on foundation. The problems is only low brightness, it's normal ?
It's a hardware or software problem ?
There are other user that have this problem ?
Thanks for disponible

Hi swolpe.
I can confirm this on my late iMac 27" i7.
The buzzing is actually the fan from what I can venture to guess. The buzzing is on the top left near the edge of the vent and is present when the CPU load is rather high for extended periods.
As others are describing, the noise is less noticeable when the screen is at full brightness vs being at the dimmest setting. If it is a fan issue, then perhaps at full brightness there is a voltage drop to the fan; which would indicate that the power supply may just be adequate.
Regardless, it is most annoying - and this is after it had replaced a new 17" unibody macbook pro (core2duo 3Ghz) which destroyed three replacement power supplies. Under heavy load in the macbook pro laptop would actually drain the battery while it had AC power. The "dead" power supply bricks would only push out ~48watts compared when brand-new when it would push out 70-80watts.
Product looks good but doesn't deliver quality .... really disappointed.
With the iMac 27" - other issues are:
The latest Bootcamp (3.1) update which had alleged Windows 7 support forced the ATI graphics driver to render in 16bit mode (did a driver rollback to revert to 32bit color).
The screen never goes in power saving mode within Windows ... never.
My MightyMouse has already burnt through 6 AA batteries in 2 months.

Similar Messages

Does all imac screen flickers at low brightness?

Hi, I just got the 21.5" imac.
I notice there's this minor flickering problem at low brightness, is this normal?
It seems like it's a known issue after I researched about it.
Is it a hardware problem or a software problem?
Should I exchange it?
Thanks for the help!

Welcome to Apple Discussions,
No that isn't normal, call AppleCare in the morning the number is in your owners manual.
Regards,
Roger

IMac 20" Core Duo - Buzzes When Running on APC BX900 Back-UPS

I pulled the plug on my APC BX900 UPS to test it, and all went fine (it showed 53 minutes remaining). I noticed though that during the 2 minutes I had the plug out of the wall (and the UPS battery was powering the iMac), I heard a buzzing coming from the iMac (sounded like it was from near the top left rear corner somewhere). As soon as I put the UPS plug back in the wall, and it switched to line power, the buzzing stopped. I suspect this may be due to the modified sine-wave that is produced when running from battery, and that the buzzing is associated with power supply components in the iMac. But, should I be concerned that during the (hopefully) few times this thing might kick into battery backup mode it's going to fry my iMac? I see very few confirmed reports of any such damage, and yes, I know a Smart-UPS (with sine wave output) would be preferrable, but if what I described is acceptable, and just purely a nuisance, I'll live with it. On the other hand, I don't want to melt this thing down trying to protect it. Thanks!
Mark

Thanks Eric. I'm not quite ready to assume the UPS is defective, although I agree it's a possibility. I have had other users in other forums report the same or similar buzzing, so I am inclined to believe my scenario is not unique. Then again, all of us "buzzers" may have defective UPS's.
I do have an APC BX1000 on another machine here at home (a Gateway PC), and I could swap them . . . what a maze of wires, etc, though. I'd prefer to avoid that too, but that might be my best course of action. Thanks again.
Mark

Macbook Pro Hard disk Makes an annoying sound (buzz) while working but functions properly.

I've got this Macbook Pro 13 inch 2.4 Intel core i5 processor. After about a year the hard disk without any reason started to make an annoying sound (buzzing) while working that sometimes quiets down but when I move the laptop it starts all over again !! Also when I put it down on a side like on my bed while I'm lying on the bed it makes the same sound !! Like when I move the laptop I can hear the buzzing sound changing !! The hard disk functions pretty well though!! What's the problem? I tried Verifying and Reparing the Disk as my father suggested and that helped a bit but after like 10 minutes it's starts again. Any ideas? Have you guys ever seen such a thing before? What should I do?

I have the same issue you're having.
When it first happened (soon after I bought my late 2013 15" MBP), eventually my motherboard and Retina display crashed and needed to be replaced. Now after a couple of months being repaired, I started getting the same clicking sounds opening web browsers or apps, etc. I'm worried its the same thing with the motherboard and or retina display starting to fail again.
Im going to have it checked out however like you said, It's hard to replicate on the spot.
Please LMK if you have any updates on the cause and I'll do the same.
Thanks!

Why does auto brightness has a bug in iOS 7.1.1 . The brightness switches automatically to higher in bright places but not returns to lower brightness in dark places but when you lock and unlock it becomes normal

Why does auto brightness has a bug in iOS 7.1.1 . The brightness switches automatically to higher in bright places but not returns to lower brightness in dark places but when you lock and unlock it becomes normal

Hello,
Same problem for me. Really a pain in the *** this bug ! Does Apple fixed it. I'm really suprised noone reports this problem and apple does not adress this.
Because of that, I cannot give it anymore to children because it hurts the view. Really a shame on the part of apple !
Regards

Sound Buzz when transferring file from Trash to desktop

I get the occasional Sound Buzz when transferring file from Trash to desktop
Its a Short "grounding" buzz similar to slowly plugging an electric guitar when the amp is on, but its loud !
I am just using the internal sound,

Brett - thanks for that input, but as stated in my original post this happens whether I do the copy within Finder, or from inside Bridge.
Your note did inspire me to try one thing though: I UN-checked my Bridge preference to export caches to folders when possible, then I went to the folder I was trying to move (on the NAS) and did Tools > Cache > Purge Cache. I found that if the folder contained only files and no other folders, then I could move the folder to my desktop. However, if the folder in question had nested folders, then I still run into the same conflict.
Question: since this conflict does not happen when moving a folder from one computer to another computer (but only from the NAS to a computer), I'm not sure how your logic holds when you say "Bridge is trying to cache the files you are moving and creates a ".BridgeCacheT" file before the remote version is copied"
To answer your other question, we use AFP or at least is says "afp://server.local" when we connect. My apologies for not being an expert on this. The icon of the NAS on the desktop looks like the icons for the other computers.
Thanks, I'm still trying to solve this. It's really become a major problem for us as we now have to drag files individually (rather than by folder) when we want to do something with them. -- Jim

Screen flicker at low brightness

Hi all
I have a macbook pro unibody 15" and I seem to be getting a screen flicker at low brightness settings.
I used to have a macbook and it never did this.
Is this normal and if not, is there anything that I can do about it?
Message was edited by: Gambit Hunt

Hi G,
I was going to suggest having it checked for the NVIDIA issue, but you state you have a unibody. If you have a new unibody, you would be best served if you posted in that forum (this area is for the Original MBP). Good luck.

I cannot eject DVD from iMac. It sounds as if it is trying to eject. I've tried onscreen eject and keyboard eject key.

I cannot eject DVD from iMac. It sounds as if it is trying to eject. I've tried onscreen eject and keyboard eject key.

Restart the computer while holding down the eject key.

Can you lower the sound of the "click" when sliding to unlock?

Can you lower the sound of the "click" when sliding to unlock?

Settings>Sounds>Lock Sounds>On/Off.
Doesn't lower it, though. Just turns it off or on.

I have an IMac and the sound is stuck on headphones when I go into perferences and try to change the sound setting from headphones to computer it won't let me switch.

I have an IMac and the sound is stuck on headphones when I go into perferences and try to change the sound setting from headphones to computer it won't let me switch.

Check out > I have no sound on my iMac internal...: Apple Support Communities
and > internal speakers not working mac mini: Apple Support Communities

My IMac has no sound...what is the problem?

I came home from a vacation and now my IMac has no sound. Any thoughts on what the problem might be?

Fixed it....restarts solved it.

I want to ask that my iphone 4 is not ringing very loudly.it is giving very low ring sound. answer me what to do??

i want to ask that my iphone 4 is not ringing very loudly.it is giving very low ring sound. answer me what to do??

rajesh.srcc wrote:
answer me what to do??
Most intelligent people would simply turn the volume up. Have you tried that?

Sometimes my hard disk makes a low crackling sound. Anything I should be worried about?

I have a Pavillion DV6 6121tx, with a 5400 RPM 640GB hard drive. I bought this laptop 3 months ago, and recently sometimes i notice a low crackling sound coming. I guess it would be coming from the hard drive only.
Should i take it to Customer Service Center?
I did do a check to see any errors by using TuneUp Disk Doctor.
Say "Thanks" by clicking the Kudos Star in the post that helped you.
Please mark the post that solves your problem as "Accepted Solution"

Firstly thank you for your reply.
Indeed, a hard disk noise is not normal and just mean the end of his life. But I know this sound well because my other computers also crack and for some of it, it's unbearable. Yet they make it since long, this has never been otherwise, and their hard disk always go good.
My problem is that the noise appeared suddenly, for an unknown reason, and according to all the software I've tested, he's always fine.
In your opinion, when I will format my hard disk to install Windows 7, it could have an effect?
Otherwise, as a last resort, I would see the service after sale of my store and then we'll see ...
Sorry for the many mistakes ...

I can't hear my phone anymore. All volumes are turned up, but very low/no sound. How do I fix it?

I can't hear my phone anymore. All volumes are turned up, but very low/no sound. How do I fix it?

Do you hear through a headset? If so, try plugging and unplugging a headset 5-10 times to free up a stuck headset mode switch. See this:
iPhone: Can't hear through the receiver or speakers

Distortion with low frequency sounds

I'm using a X-Fi XtremeGamer soundcard in a Gigabyte GA-P35-DS3L MOBO running windows vista 32bit,? and Logitech X-540 speakers with monster cable RCA cables.
About a month ago I started noticing that low frequencies (Bass drum, explosions, bass guitar) in songs, video games, etc. were being distorted and muffled. It sounds like the sounds are coming out of a massi've amp in another room behind 3ft. of concrete.
At first I thought it was my speakers, so I replaced my old set with the brand new logitech speakers and brand new cables. No help
Then I uninstalled all my creative software and drivers, and took the card out. Switched on the integrated audio chipset on my MOBO from BIOS and downloaded the latest drivers for that. The sound quality improved slightly.
Next I uninstalled the drivers for the integrated chipset, turned off, popped the sound card back in, turned off the integrated chip,? installed the drivers from the CD, then updated with the latest? SBXF_PCDRV_LB_2_5_0006 driver. Back to the original problem.
Next I checked to make sure the sound files themselves weren't corrupted, I put the same files on another computer with the same MOBO, and they sounded fine through the integrated chipset.
So I'm out of ideas... has anyone heard of a problem like this before? It seems to me I hae a defecti've sound card, but the fact I have similar problems with the integrated chipset worries me...

I have exactly the same problem - especially with the sound track in games like Far Cry2, Fear2 etc - low frequecy sound heavily distorted, just as you describe. Same result with all settings tried. Low frequecy sound in movies is fine.
I have? a 2. speaker setup, and am wondering if something is simply not seperating frequecies correctly - trying to make the subwoofer handle? frequecies that should go to the normal speakers?
Message Edited by ArchPrime on 03-29-2009 08:3 [email protected]

IMac, low brightness, sound buzz

Similar Messages

Maybe you are looking for