Ik heb dat ook. Je bedoelt het regelmatige 'vallende knikker' geluid ("KLOENK"). Ik dacht eerst dat het iets 'typisch mac' was, een of ander systeemgeluid, maar dat is niet zo. Het is wel degelijk een hardware probleem. Van wat ik er op internet van heb kunnen vinden is dit een probleem met de harde schijf, misschien wel een behoorlijk ernstig probleem (uiteindelijk kan je schijf crashen, dus ga regelmatig backuppen). De Apple poliicy schijnt te zijn dat ze er niets aan doen en dat eerst je schijf kapot moet gaan voor ze hem vervangen.
Hieronder tekst van een post die ik vond (maxfixit):
Monday, April 04 2005 @ 06:14 AM PDT
Mac mini: Hard drive “clunking,” other strange noises
With regard to odd noises emanating from the Mac mini hard drive, it appears that there are two different symptoms accompanying two separate issues.
In the first type, what can best be described as a “clunking,” light thumping, or noticeable tracking noise can be heard. In some cases, the noise is accompanied by a brief pause in system responsiveness.
This is generally resultant of normal hard drive operation, and should not be cause for concern. Many potential causes exist, including thermal re-calibration, but no drive failure should occur.
MacFixIt reader Pedro writes: “I also have heard the marble dropping sound a lot on my PowerBook 1.5GHz 15” AL. It started when I swapped the drive with a Seagate Momentus 100GB 5400RPM drive several months ago. This sounds seems to be a thermal calibration of the drive. It happens when the PowerBook heats up due to extensive processing. I normally do not see a system slow down. However, once the noise intrigued my coworkers when I was doing a presentation in a quiet conference room.
“Seagate manual has this note: ‘During periods of drive idle, some offline activity may occur according to the S.M.A.R.T. specification, which may increase acoustic and power to operational levels.’”
"I have noticed the 'Clunk ‘n Pause’ on other machines besides the Mac Mini. My Dual USB iBook does the same the thing (although the problem is less noticeable under Mac OS X than it was under OS 9) as does my work laptop, a Dell Inspiron. My understanding is that the clunk is the laptop hard drive re-calibrating itself for thermal expansion. You will notice more clunks when the machine is not getting adequate ventilation and fewer if it is. Because the OS is probably accessing the hard drive when the thermal re-calibration occurs, you will notice a slight pause as the OS waits for the hard drive to finish. Other than the slight delay, I have notice no detrimental effects of the 'Clunk ‘n Pause’ over the years on my iBook or Dell.
In the second type, the noise is much louder, and more disruptive. User descriptions include “a large marble dropping onto a hard surface.” This may, in some cases, be caused by the drive’s arm stopping due to a mechanical issue.
If your drive is exhibiting such behavior, backup your data immediately and seek diagnostic services. Many users have reported eventual drive failure beginning with such noises, which are generally astonishingly loud.
Firmware Update coming from Seagate Most Mac Minis (all that we’ve received reports concerning so far) use Seagate hard 2.5-inch hard drives. We’ve now received word from Seagate that an upcoming firmware revision will eliminate the problem, and that the noise does not – in their estimation – represent a defect in quality or sign of failure for affected drives.
John Paulsen Senior Manager for Corporate Communications at Seagate tells MacFixIt:
“This is an issue of sound only – contrary to (a portion of your report), there is no relationship between this sound and drive reliability or failure. This issue can occur with other hard drive brands as well, and only occurs with certain PC models. Seagate has a new firmware code for our drives that eliminates the occurrence of the sound, currently pending implementation into systems.”
Another possible solution: Using APM Tuner Setting the APM (Advanced Power Management) setting to the maximum using the utility APM Tuner can resolve the minor, routine drive noises in some cases.
Advanced power management systems have been known to cause occasional system delays and “clunking” noises caused by excessive parking of the hard drive heads.
Technicians: Some sounds could be early stages of drive failure Meanwhile, a number of hard drive technicians warn that specific noises may represent the early stages of hard drive failure.
John Schofield writes: "I was really struck by the description of the sound as being like ‘a marble being dropped on a hard surface.’
"I’m a former Mac tech who worked at an Apple Authorized Service Provider, now I’m doing other things. I always described that sound as “a ball bearing dropping on concrete” – a sound I heard often from drives that were about to or were in the process of dying. (I stopped being an AASP long before the Mini came out, but I’m very familiar with the noise.
“Apple won’t replace the drives until they actually die (which is a reasonable position, I think) but that means anyone with a Mac Mini making these kinds of noises should be really religious about backup – those drives could go any minute, or get progressively wonkier as time goes on.”
Adam Roberts adds: "Having serviced and worked on hard drives for almost 20 years… I can tell you that any drive making a loud clunk sound is not good… this is usually caused by the drive armature assembly slamming into the mechanical stop that limits its range of motion… which is usually caused by the fact that the servo calibration is messed up and cannot properly govern the speed and position of the head assembly on the drive…
“Basically the drives are bad… but it isn’t an instant failure… the drive will beat itself to death… whenever I hear a drive ‘clunking’ as I call it… I always advise the client to replace it ASAP. A lot of time, the problem is worsened by temperature. As the drive heats up, the electronics go out of spec and it has a harder time of keeping the servo mechanism on track. With the smaller drives in small confined spaces… they get very hot… also it just boils down to plain old bad hardware, poor quality… bad components used in the drive manufacture.”