iMac Core Duo Vibrating Hum

[danp]

Having tested the waters with a Mac mini G4, I treated myself to a lovely new iMac 17" Core Duo yesterday. I'm generally very impressed with the machine, but have one issue that I'm hoping to get some other owners perspectives on.

From the moment it's switched on, I can hear a very annoying constant hum/buzzing sound emitting from the iMac. The best way I can categorise the noise is like a muted electric razor. The noise does not change pitch or volume at any time when the iMac is switched on (be it idle, under load, reading from the hard drive, etc), and stops when the iMac is in sleep mode or switched off.

I've been doing a fair bit of investigation, and have pinned the noise down. I'm 100% certain its the hard drive causing a vibration that propagates through the metal stand of the iMac into the desk its sat on - when the machine sleeps, the pitch of the buzz changes as the hard drive spins down.

If I gently touch the metal stand or the desk area around the iMac, I can also feel the vibration. If I lift the iMac off the desk, the noise stops. If I put some acoustic insulation material between the iMac and the desk, it brings the buzzing down to comfortable levels (barely detectable). I have tried this on various solid items of furniture, and the vibration can be heard on all of them - only the insulation material cures it.

I'm interested to know if other iMac owners have experienced this, and if it sounds like a reasonable reason to enquire about a possible replacement unit?

Thanks,
Dan

 

[danp]

I guess nobody else has this problem then?

 

[Ladybug]

I just purchased a 20' Intel iMac and it absolutely the quietest computer I've ever used. No whining or high pitched sounds, no vibrations, no fan noise, etc... You should probably call Apple, as I don't think what you're describing is normal, baring in mind that I'm a new switcher myself so I don't have any past experience with Apples products other than my 30 gig iPod.

Keep us posted on how things work out for you.

 

[mikehowett]

My 20" iMac does this too, but I wouldn't really call it a problem. It definitely doesn't distract me when i'm using it or when it's on in the background. It's also alot quieter than my old PC was

 

[dmw007]

Sounds like it may be your HDD causing the vibration danp. I would call up Apple and see what they have to say about the matter. Perhaps, there is a loose screw that is allowing the HDD to vibrate.

 

[howesey]

I have the similar noise on my iMac G5 20" iSight.

It is known by many, but Apple will not fix it. It seems some of the 20" models (from my finding from the same batches) make a buzz sound from the CPU fan. It's like having my mobile phone on vibrate ring on my desk, but no quite as loud.

I have heard that a few 20" iMac Intel models do the same, but not of a 17".

 

[yoak]

My 20" has the same low humming noise. Annoying at first, but I got used to it. I bought mine online, otherwise I might have gone to the shop and asked if it was anything one could do

 

[AndyR]

This is worrying as I'm about to eBay my G4 Mini to help fund a 20" iMac...

 

[mikehowett]

My 20" iMac HDD has just this second died

 

[danp]

My 20" iMac HDD has just this second died

Sorry to hear that. I guess it would be a long stretch to suggest that the humming noise and the failure are connected in anyway, but I will definately discuss this with Apple now.

This is worrying as I'm about to eBay my G4 Mini to help fund a 20" iMac...

Although the iMac hum drives me crazy when its vibrating straight against my desk, its really much better on a mat, etc. I fully accept I'm quite fussy about the sound my computer makes (having spent £200 on trying to silence my old Athlon PC) - but for most people, I doubt its an issue.

 

[AndyR]

Although the iMac hum drives me crazy when its vibrating straight against my desk, its really much better on a mat, etc. I fully accept I'm quite fussy about the sound my computer makes (having spent £200 on trying to silence my old Athlon PC) - but for most people, I doubt its an issue.

I've got a glass topped desk so fingers crossed the iMac won't vibrate as it would echo like mad..

 

[mikehowett]

Sorry to hear that. I guess it would be a long stretch to suggest that the humming noise and the failure are connected in anyway, but I will definately discuss this with Apple now.

Thanks, but it seems to be okay now I ran the apple hardware test and nothing showed up, but it was saying it had failed in the disk utility. Just done a reinstall of OSX and now it says it's fine??

 

[danp]

Well, I just finished talking to a Support representative via web chat (v. impressed with the quality of the service).

They suspect its a hardware fault, and have recommended I either contact the supplier for a replacement or take it to a service center for investigation and repair.

As I can't be bothered to go through the process of transferring all my music, docs etc again, I think I'll take it to the service center. I'll let you all know how it goes!

 

[newmaccanada]

Well, I just finished talking to a Support representative via web chat (v. impressed with the quality of the service).

They suspect its a hardware fault, and have recommended I either contact the supplier for a replacement or take it to a service center for investigation and repair.

As I can't be bothered to go through the process of transferring all my music, docs etc again, I think I'll take it to the service center. I'll let you all know how it goes!

I have this problem to on my 20 in Intel imac. I would be curious to know what happens. I'e just been living with it to this point.

thanks

 

[macsrockmysocks]

I hear a slight hum when I wake my iMac Intel 20", but I just think it is the HDD waking up. Could that be it?

 

[XIII]

I have this problem to on my 20 in Intel imac. I would be curious to know what happens. I'e just been living with it to this point.

thanks

Ditto, I'm pretty sure I have this - just been living with it.

Let me know how it goes.

 

[danp]

I hear a slight hum when I wake my iMac Intel 20", but I just think it is the HDD waking up. Could that be it?

No, this is an ongoing thing. I know the HDD noise you mean - its much harsher, but lasts only a second.

Sounds like a number of people have had this problem. I guess you're all much more tolerant than me!

 

[hanzepans]

Simple workaround

I have the same low-level humming sound on my 20" intel iMac. I annoyed me in the beginning, but I got used to it quite soon. I have a fairly large desk, and after doing some research by ear on where the hum came form, it seemed that the hum eminates from the HD, and is amplified by the desk as if it were a large soundboard.

I found a simple but very effective workaround by taking an oldfashioned white neoprene mousepad, which I cut to have the exact dimensions of the base of the iMac. I have placed this under the base, and this greatly reduced the hum, to the point it is hardly noticable now. This may me of use to others with the same problem.

 

[danp]

Keep us posted on how things work out for you.

Thought I'd post the resolution to this issue.

I returned the iMac to the supplier (John Lewis in the UK, highly recommended).

They supplied a no fuss replacement, which unfortunately had its own problems (it would hang on boot up). Despite this, I could tell straight away that the vibrating noise I suffered with the original unit was gone.

So, I took it back (again!) and they once again replaced it no fuss. I now have a working unit that its substantially quieter than the first one. No detectable vibration in the stand at all.

So now, all is right with the world and I'm a happy bunny! Thanks for everyones help diagnosing this.

 

[XIII]

Hmm. Maybe I should send it off. But I hate the Apple return period.. and its a BTO Mac.. so.. its a bitch to return. And this is my second one anyway.. Meh.

 

[hob]

I only noticed this in the last few days when I got home for the summer break.

I diaganoised it to be the exact same thing, before reading this thread - figured it's just the desk I'm using, or the fact I'm in a much smaller room.

I just got some (clean) boxer shorts out, folded them neatly and put them under the stand. Other than the fact it's balancing a bit, the hum is almost gone.

I also get this hum with my external hard disks, on this desk. So I'm guessing it's a desky problem.

Then again, if you returned yours and it's not a problem now.... that's just annoying! Maybe I wiggled something lose in the process of moving it? gah! It's annoying when i'm trying to sleep by it...

Hob