imac 2021 buzzing noise

I don't have the base version and the problem is here...

Thank you for your feedback, I was a bit worried this could be a widespread problem...

It will never settle or change though

Did you find that a new power lead fixed this issue?

Thanks for sharing your experience at the Apple Store. It’s a bit of a bummer that they are acknowledging the issue but don’t consider it a defect.

Im having the same issue with my M1 iMac, Just wondering if anyone on here got it fixed?

I've had my M1 iMac for a few days and I can confirm than mine whines too. I'm certain all do to some extent. It bothers me a little but I mostly notice at night, or if it's really quiet during the day but not always. Funnily, only certain brightness clicks triggers it. Maybe it doesn't whine at 7 clicks, then whines at 8, then stops at 9 for example. I can live with mine because I think it's a mild case. I can see for louder ones an exchange is necessary. But I also think it's useless to have it exchanged now if the whine is faint, because until Apple changes something it's very probable that a new will whine even worse. So better stick with good enough for now.

It could be what is known as "coil whine" which from what I'm reading is normal for electronics and the noise can get quieter over time or disappear altogether.

Two weeks in I do notice it less now—not sure if it did in fact get better or if I'm not as bothered by it. I also turned off "Adjust brightness Automatically" as I found myself not needing it with my desktop environment.

I have the same issue on iMac M1 (8 Core GPU) and it is driving me crazy. My apartment is very quite and I stay up late at night, which makes the sound even more noticeable. First I thought it was the fan but now I think it is the electronic circuit making humming / hissing sound. The sound seems to be coming from the bottom of the screen, the chin, towards the centre and that's where the logic board is. It starts as the Mac is turned on and is only masked if the speakers are in use, otherwise it does not stop till Sleep / Shutdown.

Same here! I had my unit replaced and the whining sound is still there, though not so loud as it was in my first iMac M1.

I'm pretty sure it's affecting ALL new iMacs: that's a shame! I hope Apple will solve this somehow!

Agreed, sharing our experiences has been helpful. And besides this buzzing noise issue the M1 iMac has been exceptional.

I have an open ticket with Apple and they are willing to exchange it but to be honest I'm holding off for now. From what I'm reading many others have tried to exchange theirs only to find the replacement has the same issue. I'm willing to go through that hassle if I'm confident Apple has determined the issue and new replacements consistently don't have the problem.

A part of me is worried that this will be viewed as expected behavior and won't be resolved with this generation of the iMac.

Do not tilt the screen down too far and there have been instances of iMacs over heating when the screen was tilted too far down and blocked the air vents in the back with the stand.

Is it the cable or the receptical in the back? If a cable I'd ask Apple to replace it. If the receptical in the back I'd contact AppleCare for a fix or replacement.