Strange and annoying fan noise in brand new iMac 27" 2020 (incl. audio file)

[lancee_xyz]

Hi,



I just replaced my late 2013 iMac 27" with a 2020 model to get the Big Sur experience

Unfortunately my new iMac sounds strange - the fan make a clacking or engine like sound all the time when running at lowest RPM. iMac is 10 days old and does it ever since.
Is this normal? I hope not its annoying and my old iMac didn´t do that...

Listen here: https://www.dropbox.com/s/1mvw1t6r05efcnq/fan sound.mp3?dl=0


Regards
Dominik

 

[index_cards]

I'd consider returning it if I were you. I had an issue with a noise emanating from my 2020 iMac and when I got it back from Apple, the microphone was broken and the noise wasn't fixed. I then took it to an Apple Authorized Service Provider and they scratched the screen, dented the bottom, set the display about 0.5mm off center, and didn't fix the microphone or original noise. Apple made an exception to their return policy, took it back, and gave me a full refund, but the entire process took a little over a month because of COVID...

 

[LadyNinja]

YES! I think I have the same sound! Finally ?
Brand new, there was a sound on startup, like a real fan blade sound. It went away after 2 sec.

After repair it came with a new sound!

But after reseting smc several times, the sound is not as loud. And on top off that (yes I have had my head into the back machine for some time know.....) the sound comes and goes!!! Literally when doing nothing.
I have already contacted my shop, they still havent replied. But im thinking if i maybe should wait it a little out. Dont know how I should present the problem... But I have the sound recording.

There is two different methods of a smc fan reset. Dont know if its kinda the same or.... The one is unplug power cord, the other is holding the power button for 10 sec.

Aaaaand, I found a youtube video from an macbook user. Comments said smack it! And so funny, so many others replied the same that it actually worked. Kinda difficult do smack the imac... But maybe try a little bump, or tilting the screen some times.



Heres the same sound as yours, i think. (dont mind the high pitch)
Fan issue

This is how it normally sound. This is the correct sound for all imac, only the sound of air.
Normal fan sound

Aaaand heres my first fan issue. This one is now fixed.
Fixed

 

[lancee_xyz]

hmmm, the question for me is: is it normal or not? If yes I´d rather get another model, an older one maybe. If not I want a replacement. I still can give it back.

I cannot play your audio unfortunately

 

[LadyNinja]

hmmm, the question for me is: is it normal or not? If yes I´d rather get another model, an older one maybe. If not I want a replacement. I still can give it back.

I cannot play your audio unfortunately

No, not normal return if you can. I'll fix it tomorrow.

 

[CheesePuff]

Nope not normal at all my 2020 27” inch is silent

 

[LadyNinja]

I have updated the audio

 

[lancee_xyz]

Thanks - it is very strange - it seems like its coming sporadically - sometimes after 5mins - this morning after 2hrs of working... I now use some micro fiber cloth to block the vent... now is quiter

...and it seems that it is independent from the fan rev.
As far as I know the iMac has only 1 fan? Correct?

 

[LadyNinja]

Thanks - it very strange - it seems like its coming sporadically - sometimes after 5mins - this morning after 2hrs of working... I now use some micro fiber cloth to block the vent... now is quiter

...and it seems that it is independent from the fan rev.
As far as I know the iMac has only 1 fan? Correct?

Mine is also independent from the fan rmp. Have macs fan control and it dosent get louder with higher rmp.
Yes its only one fan, think its just off center to the right, from the front view.
Would not recommend blocking the vent. The air goes in from underneath the display, below the apple logo, and out in the back.

In may can it is the same, with the sound just suddenly showing. It can be from the startup, other times I just feel some buzz sound, inspecting the imac, and yes it has started. As I said, mine sound has dropped to almost nothing.
Previously I returned the retina display. Totaly waited 10 weeks to get an working machine, then this one needed repair. I have reported the problem, I have good warranty in my country, as well as apple care. So I will monitor it closely. But for all other ppl I would definetly return it. Dont know if I would even do a smc reset. Then you may be in my situation, where the sound drops down, but may still be present, and the folks at apple thinks you´re mad.... Guess theyll do a smc reset them self. But I would at least first open a case on it.
Wish you good luck, please update

 

[lancee_xyz]

@LadyNinja - how did you finally get rid of it? Multiple SMC Resets? Or send it in to Apple? I live in Germany - where do you live? I have until saturday to give it back - we have 14 days return policy in Germany.

 

[LadyNinja]

Norway. Yes I took several smc resets. But im still not sure of witch method one should use. So i tried both. Theres one for imac desktop, and one for the imac with t2 chip. So I guess the second.
I discovered the second method the same days as big sur came. First I tought it was all gone with the big sure update, but it was not. Its like, it got quiter after smc reset, but a little more after big sure. laughing....
I think its just coincident. I would bet its the fan somehow touching some parts. It may be loose in the middle part (the drive thingy in the middle where fans attached). I know for a fact, that the sound can come and go without moving the machine or using it, but theres always background task running. Soooo.... that may on the other hand relate to smc. Ha, best guess is both.
Mine is like this AFTER a repair. So the fan should be good. But reading here on the forum that ppl think the fans are at lower quality than before and from different places/vendors.
You could also get it repaired. I hope its juste something a little loose. I search for the macbook video.

 

[LadyNinja]

fan noise macbook read the comments

Could at least unplug the machine and turn it a little around. Thats not any more than it would be under shipping.

 

[LadyNinja]

Is the fan kicking in after waiking up after sleep? Or under the startup.
I can clearly hear mine in around 2-3 second. Louder than the standard fan noise, it settles down afterwards.

Could any others reading also answer this please?

 

[lancee_xyz]

It used to kick in a couple of minutes or few hours after start or wake up when working normally.
The sound is gone since yesterday... it is a brand enw Mac - maybe some dirt from production caused the sound. I did smack the Mac but it did not solve it immediately - i did 2-3 SMC resets though.