C2D iMac 24" and hi pitched whine & rhythmic buzz

[designed]

Heya,
after a stormy start with my 24" iMac* I noticed another problem. A high pitched noise coming from it, not unlike the noise a warming up TV makes or what you hear when your ears lock up. The noise is quite strong and is more audible when a bit sidestepped from the iMac.

In addition there's an occasional rhythmic buzz which occurs as 5 second buzz, 10 second silence and then again a 5 second buzz (times are approximate and do vary a bit). The cycle repeats a few times and shuts up for whatever period of time (10min? 10 hours?).

I was wondering if anyone else has had these? One other person in the Finnish Mac user forums has had the hi pitched whine, he had his power supply unit changed (or he should have, instead they exchanged his machine).

* = I contacted Apple the next day I had unpacked my 24" because it has 3 stuck pixels, two dim red ones near the edges (I barely notice them myself) and one BRIGHT red in the dead center of the display. Apple declined to exchange the machine, mostly because the service people couldn't first find anything wrong with the display, then they saw the bright red center one and decided that they won't do a thing because of 1 stuck pixel (regardless of the placement). In this light, I am all for the "change the unit".

 

[Kiscokid]

it's hard to comment on noise levels.....I have always used incredibly noisy PC's and I find my 24iMac relatively quiet. There is a slight humming noise with a mild whine - but surely that's acceptable - I guess it's a fan. is there such a thing as a silent machine?

However the fact that your noise seems to be intermittent would suggest that there could be something sinister at work perhaps....

 

[designed]

Yeah, I've used some pretty noisy PCs in my time but this is different sort of noise. I'd say the hi pitched whine comes from the power supply and the buzz might come either from a fan or the hard drive, neither of which should sound like that.

I'm taking the iMac into service tomorrow morning, hope to get it back soon(ish).

 

[volk]

I have the humming, but that doesn't really bother me much. I have a fan, though, that is driving me crazy. It seems to be causing a vibration that resonates over the entire machine. I'm sure I could fix it myself, but I don't want to open the machine and void the warranty. I am still deciding if it is worthy of repair or not.......

 

[skunk]

My 24" is incredibly quiet. I've never heard the fan, and I can barely hear if the machine is switched on. This is how it should be. It's quieter than my Cube or my Mini.

 

[bimmerkid]

Re:

Hey,

I just purchased mine the other day and I have the whine as well. It only happens when the display is on sleep (not the computer). It's really annoying when your in an extremely quite environment.

 

[skunk]

Sometimes I get the impression I'm the only one with a quiet machine.

Or possibly I'm deaf.

 

[lasse.a83]

Heya,
after a stormy start with my 24" iMac* I noticed another problem. A high pitched noise coming from it, not unlike the noise a warming up TV makes or what you hear when your ears lock up. The noise is quite strong and is more audible when a bit sidestepped from the iMac.

In addition there's an occasional rhythmic buzz which occurs as 5 second buzz, 10 second silence and then again a 5 second buzz (times are approximate and do vary a bit). The cycle repeats a few times and shuts up for whatever period of time (10min? 10 hours?).

I have the axact same noise.
I posted a thread in applediscussions forum:
http://discussions.apple.com/thread.jspa?threadID=737036&tstart=0

I was wondering if anyone else has had these? One other person in the Finnish Mac user forums has had the hi pitched whine, he had his power supply unit changed (or he should have, instead they exchanged his machine).

I think that finnish guy in forum (hopeinenomena.net) had the buzzing for continuely (not randomly repeating), it was not the same buzzing

I had this exact same noise in my pc. I really think its comming from the powersupply. I have not noticed the noise when monitor is turned off, think because the power effect is less. Maby the powersupply starts buzzing when imac takes more power from it.

It could also be the hardrive or anything else off course, but i dont think so.

Tilting and pusshing/pressing the case will not help. the noise is really hard to find because it only lasts for few seconds.

 

[Zwhaler]

My iMac has a very faint high poiched noise coming from the top left cornet (on the back) but only when it is put into sleep mode. I went to the Apple store about it, and the guy said his G5 iMac does the same thing, so I let it slide.

 

[austincolby]

Rythmic low throbbing from my new 24" iMac

I'm also experiencing some weird noises. Luckily, they are pretty quiet, ie you have to be in a quiet room to hear them, but nonetheless they are annoying, and I am afraid they might portend some other issue.

The noise started as a rythmic rattling in the back- I thought there was a lawnmower outside my window moving around, back and forth- it would rattle for a few seconds, then stop for a few seconds, then come back for a few seconds, then stop... etc.

That has stopped (for the time being) only to be replaced by something quieter, but actually more annoying. Basically, now, it does a very low-pitched moan every few seconds, lasting for maybe 2 or 3 seconds, on and off, on and off... its so low pitched that you almost feel it as much as you hear it.

Beyond that, however, I have one other concern- this thing is NEVER quiet. At all times, it sounds like the fan is running, constantly, with a low whooshing of air. This concerns me because Ive heard a lot of other people describe their new iMac as dead silent.

Any ideas for me? Is this something I should be taking my system in for?