This past article is being re-posted and continuously updated on this Wordpress-powered blog so people can post comments and questions. This article was originally published in December of 2008.

My most recent and fresh complaint with Apple has to do with an annoying clicking sound coming from the hard drive (HDD) of my early 2008 Macbook. This is not to be confused with a much louder and constant clicking sound of a soon-to-fail HDD. This is a more subtile, yet annoying click that is most obvious when the computer is not under heavy processing use. I just purchased this product directly from Apple as a refurbished unit. Although the machine is technically a refurbished unit, it is actually completely new, at least the HDD was, as that is easy to check. This “click” sound is yet another example of when a “bug” is actually considered a “feature.”

It turns out that this “clicking” is part of a “power management system” that functions to save energy and reduce temperatures. For every “click” what’s happening is the heads of the HDD are parking, and the disk platters begin to stop spinning. But then the HDD’s heads quickly unpark, and then park again, and then unpark, and sometimes this happens every couple of seconds and becomes very annoying. It is most especially annoying when using a notebook computer in a very quiet setting. The click(s) can sound just like a ping pong ball being dropped on a hard surface.

This problem is most recognizable when one’s computer does not have many applications in use, and is sitting in a fairly idle state, like when one is trying to read from a website through a browser, and not doing much else that will tax the CPU and the HDD. It is when the computer is in this state that the HDD manufacturer’s (or is it Apple’s/*nix’s) power management system and the Operating system seem to not get along too well, and then come the click, click, clicks. What is most bizarre to me is that the clicks are somewhat random, at least to my limited knowledge. Sometimes, in what appear to be similar computer-use situations, there will be clicks, and sometimes no clicks.

This problem actually occurs on all Operating Systems based on Unix/Linux, including the Mac OS. As far as Windows is concerned, many say this problem does not exist, and some say it does. The folks who say that Windows Vista is not plagued with this problem claim it is because the OS accesses the HDD so very often, like every 4 seconds at a minimum, the HDD’s aggressive power management scheme never has a chance to kick-in and sleep the HDD and park the heads. Whereas the Mac OS Leopard 10.5 may access, or touch, the HDD every 8 seconds at the least, allowing the HDD’s over aggressive power management to sleep the drive (hence park the heads, and make an audible “click”) every few seconds. The same seems to apply to open source distros of Linux, however they seem to be on top of a fix. Maybe this is because the average linux user is quite computer-savvy, unlike today’s average Mac user.

This issue is not just about an annoying noise emitting from the HDD, all those clicks might be drastically shortening the life of the HDD. To computer geeks each one of those annoying ping-pong ball sounding clicks is known as a “Load_Cycle_Count” and every HDD manufactured has a limited number of allowable load cycle counts before the HDD fails! My particular drive will fail at around 600,000 load cycle counts. that number may seem high, but considering that the HDD in question is already at 22,731 “clicks” or load cycle counts (this number is easily ascertainable with the use of specific software) in under one month’s use, well, do the math. My HDD is pre-programmed to fail in 2 years. Many people have reported a much higher rate of accumulated “clicks” than my HDD has. I have an old external 80 gig firewire HDD that is running strong after 8 years of use!

The big mystery here is who is to blame? It is either the OS manufacturers, i.e. Apple, Windows, Ubuntu, or we need to look at the manufacturers of the HDD’s themselves. I actually think they both are to share the blame.

There are numerous forum threads running all over the web about this issue. Here are links to some of the best:

http://ubuntuforums.org/showthread.php?t=591503
http://forums.macrumors.com/archive/index.php/t-258751.html
http://forums.msiwind.net/general-discussion/advent-4211-making-clicking-noise-t863.html
http://discussions.apple.com/thread.jspa?threadID=1226956&tstart=15

UPDATE: Starting to wonder if this will be one of those extremely annoying “bugs” that will never be fixed in 10.5.x, thus forcing us to buy Snow(Job) Leopard? (Pun intended). One of the key OS functions being “improved” upon with Apple’s “Snow Leopard” OS 10.6 due to be released next year is “Power Management!” I am starting to think the real fix will be purchasing a still-too-expensive solid state Hard Drive.

The clicks are annoying as all heck in a quiet room! None of the “fixes” to be found on the web seem to work, none!

1. HDAPM, nope. (OK, this one works, see below)
2. declunk, nope.
3. APM tuner, nope.
4. Turning off “put hard disk to sleep whenever possible,” nope.
5. disabling the motion sensor, nope.

this problem has been around a long time! None of the various discussions on this issue seem to come up with a workable resolution. What the heck, Apple?

UPDATE 2:Originally Posted by csupinski at Macrumors.com

“The noise you are all hearing is normal, the hard drive parks itself when it thinks it’s in a free-fall in order to prevent damage to the platters if the heads were make contact. The way I look at it, if I drop it, it’s probably not going to work anymore anyway so why do I care if the hard drive has a free-fall sensor?

Look in your System Profiler and you’ll see this line at the very bottom of the “Hardware” section. “Sudden Motion Sensor State: Enabled”

This link will give you more information if you want to disable it.

http://support.apple.com/kb/HT1934

My response: There may be something to the idea that Leopard’s power management and Leopard’s “Sudden Motion Sensor” may conflict each other just a bit. I have disabled the Sudden Motion Detector and I seem to be hearing less audible clicks. I was under the impression that I had tried this before and it did not work. However, maybe I was unsuccessful in actually disabling the SMS, or I re-booted and lost the settings without realizing it, or I needed to do a few more specific adjustments to the sleep settings of the Macbook to get everything just right.

EDIT: (AFTER 2 HOURS OF TESTING) It seems that I am still getting SOME clicks, but not quite as many, and not in that rapid-fire, click-every-4-seconds annoying way. Yet another reason to sleep, and not shut down, at the end of the day–unless one feels like resetting the SMS at each new startup...(actually, the SMS settings seem to hold after a shut down and re-boot!)

THE EXACT SPECIFICS: I am under the impression that what made this fix actually work this time had to to with a few specific things I did differently in addition to simply disabling the Sudden Motion Sensor (SMS). First, I went into System Preferences’ “Energy Saver” and set the computer to never sleep either the CPU or the display for both AC power & battery power, and made sure “put HDD to sleep whenever possible” was not checked. Second, using MacPilot’s “Hard Disk Power Manager” unchecked “enable sudden motion sensor” for both AC and battery power, and double checked that HDD were set to never sleep, which is accomplished by moving the sliders in Macpilot all the way left, (as opposed to 120 minutes or any other time in minutes), for again, both AC and battery power. The SMS can also be disabled with the Terminal using the technique in the link to Apple support documents mentioned above.

Many may be thinking “never put your computer to sleep?!?!” No, I am saying never let your computer put itself to sleep automatically. I put the notebook to sleep all the time–manually, by clicking on the Apple menu. I do not mind doing this, in fact it is my preferred way. My Apple notebook is used as a desktop replacement in clamshell mode about 95% of the time, another reason why I do not mind having any predetermined sleep settings for HDD or CPU and disabling the Sudden Motion Sensor. Any method to get rid of those highly annoying, random, rapid-fire ping pong ball bounces that is neither exceptionally difficult to achieve, nor voids my notebook’s warranty, makes me a happy computer user! Something to note is that my “Load_Cycle_Count” continues to increase at a steady, yet acceptable pace, yet there is not the corresponding HDD “Click” accompanying the numerical increase in my HDD’s load_cycle_count. So I must admit that there may not be a one-to-one relationship between an audible click of the HDD and a numerical increase in my load_cycle_count. Nevertheless, the loud, repetitive “clicks” have left the building! I am starting to believe that this whole clicking business may be reduced to a conflict between the “Power Management System,” be it the operating system’s and/or the HDD’s, and Leopard’s “Sudden Motion Sensor.”

This fix is not exactly Ideal for most Apple notebook users, as most like or have to be mobile with their Macbooks / Macbook Pro. Disabling the SMS is not a great option for most. But it could be done temporality when using your notebook computer in a setting where it will not be moved around for a while. I still think Apple needs to fix this. But they might not. The clicking noise is just loud enough to annoy the sensitive type and just quiet enough to be ignored by most.

UPDATE 3: Another new day, today being Tuesday, December 9, and I think my Macbook’s hard drive is intermittently clicking again! Noooooooo! I give up. Apple, Fujitsu, fix this for me. The HDD is clicking but maybe not as often, sure, that’s right, it is not clicking as often. Anyone who tries the band-aid fix above, please e-mail me, and let me know if you had any amount of success in ridding your notebook of the hard drive clicking. Drop me a line at info@dougitdesign.

While I do think the “fix” outlined in UPDATE 2 had some minimal effect on reducing the overall number of “ping-pong-ball-bounce-esque” clicks emanating from my Macbook I still decided to take this up with Fujitsu, the maker of the 250GB HDD in my Macbook. Dialed up some live chat with a Fujitsu rep., here is how it went (spoiler alert: not so great):

Please wait while we find an agent to assist you…
You have been connected to Giancarlo .
Giancarlo: Welcome to our FCPA live chat service. How may I assist you?
Doug A: This HDD in question, combined with Apple’s Mac os 10.5.5 is a MAD CLICKING thing………..
Doug A: APM? / firmware tool is needed bad
Doug A: hitachi makes a tool to help correct this, why not fujitsu?
Giancarlo: What is the part number of the drive that starts with a CA0
Doug A: huh?
Doug A: Capacity: 232.89 GB
Model: FUJITSU MHY2250BH
Revision: 0081000D
Serial Number: K43XXXXXXXXX
Native Command Queuing: Yes
Queue Depth: 32
Removable Media: No
Detachable Drive: No
BSD Name: disk0
Mac OS 9 Drivers: No
Partition Map Type: GPT (GUID Partition Table)
S.M.A.R.T. status: Verified
Giancarlo: Where did you get the drive?
Doug A: OEM, earily 2008 macbook, Apple
Giancarlo: Had a feeling just looking at the firmware revision.
Giancarlo: Any firmware requests would need to go through Apple
Doug A: so you have nothing for me?
Giancarlo: I’m sorry I do not. Apple (and other companies) take our drives and flash their firmware on the drive, thus taking ownership of that aspect
Doug A: Thanks. It’s official folks, Fujitsu is “passing the buck” and not taking ownership on this issue (for my blog).
Giancarlo has left the session.
Your agent is experiencing technical difficulties. Please stand by while we re-establish contact or find a new agent...
You have been connected to Giancarlo .
Doug A: So, this has nothing to do with an over-aggressive Power Management System that is built into the drive itself?
Doug A: Are you still here?
Giancarlo: I’m sorry I have nothing regarding this
Doug A: How about a manager?
Doug A: i.e. your supervisor. Are you still with me?
Giancarlo: I’m looking for one that is available
Giancarlo: I’m sorry I’m not getting anyone available at the moment but I can do the next thing and send this over to engineering to see if they can go through some channels
Doug A: My email is dougit@ymail.com I would really like some answers to this. Apple does not want to take ownership on this situation that seems to be some sort of conflict between your HDD power management, Apple’s Sudden Motion Sensor, and something? Linux suffers from this same problem, so HDD manufacturers need to take a bit of ownership on this widespread problem. There are forum threads all over the web about the HDD clicks!
Giancarlo: Okay I’ll pass this on to engineering and see what they have to day
Giancarlo: I mean say
Giancarlo: Sound like a plan?
Doug A: I will be waiting for an answer. thank you. If I hear nothing, I’ll be back to inquire some more, OK?
Giancarlo: Very good
Doug A: document and save this session for further reference, OK
Giancarlo: It already is
Your session has ended. You may now close this window.

OK, Apple, it looks like the ball is in your court…

UPDATE4: Fujitsu, the manufacturer of the occasionally-clicking hard drive in question, has officially washed their hands of this problem. I received an e-mail from them this morning. This is what the contents of the communication were:

Mr. Dougit, I sent the inquiry to my engineering contact who also consulted with a couple of others; one of the a Macbook user himself. They are not aware of any problem with the M120 using APM with Apple’s Sudden Motion Sensor. There also have not been any new Firmware that exist. They say, “Use of any of the three APM modes should not cause the drive to make clicking noises.” Best regards, Giancarlo, TSE Sr.

I guess it is time to start dealing with Apple. But I know what they will do. Aple will simply pull the drive in question, and throw another brand into my Macbook, and the different branded drive will, most likely, also click. As I presumed before, this is not an issue with a specific HDD manufacturer, this is an issue with the Mac Leopard OS, or is it? The Fujitsu rep. did seem to become befuddled the moment I mentioned “an over-aggressive Power Management System that is built into the drive itself.

UPDATE 5: (12.16.08) Today I successfully installed HDAPM. I know that it is successfully installed because using a free open-source app. called Smartctl (this Apps seems to not work with Snow Leopard 10.6!) I can see that my load_cycle_count is not increasing! I also noted that I cannot hear the unique “whirling” sound of my notebook computer’s hard drive changing speeds, i.e. the spinning-up and spinning-down of the platters. I also cannot hear the dreaded clicking sounds any longer. Basically, with HDAPM, I have set my HDD to maximum power / minimum disk “spin down” and head-parking. Heat is not an issue at all; using a great utility called iStat menus, I have seen absolutely no increase in the temperature of my HDD, or any other part of the computer.

Installing HDAPM is fairly easy for anyone who is used to tinkering with their computer, just be sure to follow the instructions that can be found on the internet with a simple search. I had to do steps 9 & 10 of the HDAPM install, which require one to download an application called Ligon, and create a new .plist (preference file) for HDAPM. The load_cycle_count of my hard drive is now stopped at a “raw value” of 35,969 after 720 hours of use.

THERE IS ONE PROBLEM WITH THIS–sort of, after rebooting the notebook computer I realized that HDAPM had reverted to its old ways for me, with a console message that HDAPM failed, not supported. I was able to reinstall HDAPM after I deleted the /usr/local/bin folder and the HDAPM app residing inside of it, as well as the HDAPM .plist that was in the library/launchdaemons folder, rebooted, and did all the same steps to originally install HDAPM on my notebook computer. What a PITA! Not sure if I want to do all those steps every time I reboot…but it is the only solution I have found to get control of all the hard drive clicking and the rapidly increasing load_cycle_count.

UPDATE 6 (12.20.08-FINAL UPDATE!): I got an email from “Felix” who provided the final piece to this puzzle. He recommended that I place HDAPM in a slightly different location: /usr/bin, NOT /usr/local/bin. After doing this, HDAPM continues to work across reboots and restarts. I decided to even ditch the launch daemon .plist and just type “hdapm disk0 max” in the Terminal after any reboot. So, for all of you out there who have this problem of HDAPM not continuing to work after a reboot, remove all parts of it like I stated in the paragraph above, restart (maybe go ahead and zap the pram–hold down Option-Command-P-R until you hear 3 chimes) and then reinstall HDAPM in this slightly different location. It should work, it worked for me. YES!

UPDATE 7 (12.31.08): HDAPM stopped working! I have not downloaded any OS updates or Security patches between update 6, eleven days ago, and now. Not sure how, but about 3 hours before Midnight I began to hear disk clicking sounds. They may have starting happening earlier in the day, when it was much noisier, not sure exactly. Went into the Terminal and entered the command “hdapm disk0 max” and for the first time in 11 days Terminal gives me back the message I thought I had done away with, “Setting APM level to 0xfe: FAILED: APM not supported.” Do not know what to think except–fail, NO! (Maybe I will try declunk again!)

UPDATE 8 (01.02.09) I decided to leave HDAPM where I last installed it because it did not hurt anything by it being there. Today, for kicks, I typed the “hdapm disk0 max” command in the Terminal. For whatever reason, it worked again, giving me the message “Setting APM level to 0xfe: Success.” Not sure what to think now. I did do one system change, using Little Snitch, I denied allowing an outbound connection by automountd, which was trying to connect “UDP connections to port 111 (sunrpc) of mach_kernal.domain.actdsltmp” I have no idea if that outbound connection has anything to do with HDAPM working or not. I do find it odd how HDAPM seems to wax and wane in its ability to work…?

UPDATE 9 (01.14.09) I wanted to post a final update and, what seems to be a resolution for this HDD issue. I have left hdapm set up in the same place that I put it 3 weeks ago–see update 6. Also, with the help of Little Snitch, I am still denying the specific outbound connection attempt by “automountd” mentioned just above in update 8. What I have found is that if I do a reboot or restart and attempt to load hdapm in the Terminal, hdapm will say it is not supported. The Terminal will continue to give the message that hdapm is not supported over numerous reboots and restarts. However, if I shut down the computer–as in, yes, a complete shut-down that requires you to hit the physical start button of your computer to start it back up–and then enter the command in the Terminal to start up hdapm and set it to maximum performance, it works every time. I am certain hdapm is working because all disk clicking goes away and my load_cycle_count is not increasing, except for when I choose to sleep my computer and the load_cycle_count will increase by 1. I must reiterate that I am not actually sure if denying “automountd” to connect with port 111 (sunrpc) of mach_kernal.domain.actdsltmp had anything to do with my eventual fix, but have not noticed any detriment for denying that specific outbound connection.

In conclusion, I must say that I know many people out there had a much easier time installing hdamp–lucky you. However, there are many people who were, or are, having a difficult time installing hdapm. A few newer oem HDDs that are common in Apple’s MacBook/Pro computers, like my Fujitsu, tend to be more difficult to get hdamp up and running on. Hopefully this long blog article can shed some light on the process for those of you out there having to wrestle with the annoyance of a soft-clicking hard drive. Also, hopefully the next Mac OS X update does not send me back to square one.

UPDATE 10 (09.03.09) HDAPM has continued to work on my laptop through the OS X Leopard 10.5.8 update and also successfully works with OS X Snow Leopard 10.6. Occasionally with a reboot / restart the Terminal App will say “Failed APM not supported. However, every single time I shut down my Macbook and restart it with the power button HDAPM always loads successfully with the Terminal command “hdapm disk0 max” or, which ever other version of that command I choose to use, Like “hdapm disk0 250.”

UPDATE 11 (11.13.09) I am currently running an Apple Macbook 5,2 (2.13 C2d, 250 GB Hitachi HDD, 4GB, 9400) and Snow Leopard 10.6.2. I no longer have any need for hdapm on this computer, as there is no clicking HDD in my current configuration. Whether it is the different model of HDD, different computer, a more matured Apple Mac OS X—now at 10.6.2, or a combination of any of these options, I have absolutely no clicking HDD. After 2 months of average use—550 actual hours—the HDD has roughly 3,500 load cycle counts, or an increase of 1 load cycle count every 10 minutes, which is extremely reasonable. Again, this is with no HDAMP, Sudden Motion Sensor is enabled, and put hard disks to sleep when possible is checked! It is important to note here that this Macbook is completely factory stock—all the memory, the hard drive, and everything else…but especially the hard drive which matters here the most—Apple factory stock.

UPDATE 12 (01.04.10) In addition to the MacBook mentioned above, I am also now running an experimental setup in the form of a Dell Mini 10v with OS X Snow Leopard 10.6.2. The HDD in this Dell Mini is a Western Digital Scorpio Blue 160GB (WDC WD1600BEVT), and it is very loud. Not the traditional soft-clicking that is all too common with anyone on a quest for HDAPM information, but more like random seek movement and other “R2D2-Sounding” noises. These noises happen about every 5 seconds, or so. After one month of average use (250 actual hours) the HDD has roughly 28,000 load cycle counts—which is a lot of head parking, but not enough to equate each HDD noise—that happens about every 5 seconds on this configuration—with a load cycle count. Doing the math, I am receiving a load cycle count increase of 1 about every 30 seconds.

After trying every trick in the book, I think that HDAPM will not work with this setup. I also think Apple fixed clicking/noise  for most of the HDD’s that come with newer stock Mac configurations—See my Update 11 above, and execute a Google/Bing search for Performance Update 1.0 or Hard Drive Firmware Update 2.0 the Performance Update had a short-lived life for Snow Leopard users, as it has been rolled into the 10.6.2 update (not sure about Leopard 10.5.8 users)—I assume the Hard Drive Firmware Update 2.0 has also been included in the 10.6.2 update, but I have not done the specific research to validate this guess. One can still download the Performance Update from Apple and dig into its contents with the app “Pacifist.” doing this reveals that Apple made changes to the IOAHCIFamily.kext, specifically the IOAHCIBlockStorage.kext…

The MacBook 5,2 (2.13 C2d, 250 GB Hitachi HDD, 4GB, 9400) mentioned above is whisper-quiet, even with the sudden motion sensor enabled, even with “put hard disk to sleep when possible” enabled, and even with no HDAPM installation. This Macbook does have the Performance Update 1.0 installed, however. I purchased this MacBook 5,2 right around the same time the Performance Update 1.0 came out, so I never got the chance to see if this configuration exhibited a noisy hard drive before the HDD Performance Upgrade 1.0 software update.

However, if you upgraded the hard drive in your MacBook, MacBook Pro, MacBook Air, and possibly even MacMini with an aftermarket 2.5 inch HDD, or if you are running some type of  experimental setup, you may still, to this day, be confronted with excessive HDD clicking, beeping, grumbling, seeking, head-parking and load cycle counts under OS X Snow Leopard (or Linux, or Windows on any computing device using a 2.5 inch HDD, as this phenomena is certainly not limited to Mac-Snobs).

The Dell Mini with OS X 10.6.2 will not allow for HDAPM to be functionally installed. The netbook keeps getting the old “Setting APM level to 0xfe: FAILED: APM not supported.” I cannot get HDAPM to run on this setup under any circumstances. I also tried to use the Performance Update 1.0 on the Dell Mini but got the dialog box stating that my computer does not have eligible hardware.

With the Dell Mini 10v running OS X Snow Leopard so well, it is hard to gripe very loudly about a hackintosh with a slightly-loud drive that can only be heard late at night, when all is quiet. But with no fan and no optical drive, having a perfectly quiet hard drive—I don’t mind the slight sound of the platters spinning—would make this late-night, OS-X-Snow-Leopard-Powered, netbook-romance all the more hush-hush…

UPDATE 13 (01.08.10) I am now under the belief that HDAPM does NOT WORK with a clean install of Snow Leopard 10.6.2. At least not on a Dell Mini 10v with SL. If you happened to end up at 10.6.2, and migrated your old settings from 10.6.0, and maybe even 10.5.X, then HDAPM might work, if you are lucky.

I think Apple may have purposely disabled HDAPM, and at the same time fixed adjusted most of the excessive HDD clicking, beeping, load cycle counting, head parking, and seeking for (most of) the 2.5 inch stock OEM drives shipped with their machines, and only those drives.

By implementing both of the above ideas (1. disable HDAPM and 2. Fix ONLY its stock OEM drives) is Apple exerting more of that new-school, covert, all-inclusive control? Come in Apple, now we cannot even upgrade our HDD’s without them becoming clickers?

(I may have to try an experiment, and replace the IOAHCIBlockStorage.kext from Snow Leopard 10.6.2 with the IOAHCIBlockStorage.kext from a “Pre-Performance Update 1.0″ Leopard 10.5.8 system, and see if HDAPM will work again…Or you could try this and post a comment!)

UPDATE 14 (01.19.10) I tried my idea just above of replacing the older BlockStorage kext and it made no positive difference…

UPDATE 15 (01.21.10) Today I made a couple of changes to the OS X Snow Leopard 10.6.2 setup on the three computers in my family that run Snow Leopard—a 2009 Macbook, 2009 Mac Mini, and a 2009 Dell Mini 10v. I made two system changes, with two different positive results. I am not sure what fixed what, as I made these system changes simultaneously. First the bullet points, then the long explanation…

CHANGES:

• Uninstalled LaunchAgent called “Antipop”

• Installed Snow Leopard 10.6 latest Security Update 2010-1.

POSITIVE BENEFITS:

• Auto Sleep now functions on  all 3 SL-equipped computers. Auto sleep had been non-functional on all three systems. I could manually sleep my systems,  and the screen would auto sleep at the set time, but the computers themselves would not auto sleep.

• HDD (hard drive) on the Dell Mini 10v is much more quiet! Before the two changes above, The Western Digital Scorpio Blue HDD in the netbook was making little chirps, clicks, seeking movements and other odd sounds nearly every 5 seconds. Now, this drive will go 30 seconds to a minute without any loud noises! This is without HDAMP installed, as HDAPM continues to not work with the Dell Mini 10v & 10.6.2.

Now for some details. First, I downloaded the latest version of an app (technically, a LaunchAgent) called “antipop” and used its own UNinstaller script to completely UNinstall the few different parts that make up that LaunchAgent. Antipop works, and I used it on all of my OS X systems going back to 10.5. However, and I am not completely positive about this, I think Antipop may disrupt an OS X Snow-Leopard-equipped computer’s ability to auto sleep. Here is exactly what Antipop accomplishes, quoted from the developer’s website:

antipop is a LaunchAgent designed to prevent Mac OS X from turning off the sound system. On many laptops (particularly on MacBooks and MacBook Pros), the sound system emits an audible pop or click when it goes to sleep. This is particularly noticeable when a low-impedence or externally-amplified device is plugged in to the laptop’s line-out jack — users with sensitive headphones or amplified speakers often hear this pop when Mac OS X puts the laptop’s sound hardware to sleep after 15-30 seconds of inactivity. This software stops this pop from occurring.

Antipop may not be an issue for most, in and of itself—I have not heard of a large number of folks using antipop having autosleep issues. (Then again, I have not heard of many people using Antipop at all). However, in some unique circumstance, the LaunchAgent Antipop might cause some autosleep issues. For instance, if a certain file of antipop had been deleted, but not all the files for the app were deleted, part of the app might continuously call out for the missing “other part” of the app, and keep the computer in a continuous working-state, preventing autosleep. Hence, using Antipop’s own uninstaller—it does a complete job of uninstalling all the parts that make up the app/LaunchAgent.

I may re-install Antipop on one of my systems to test if it was an issue, however for now I am too content with my new system fixes to mess with Antipop at this point. Thing is, My speakers seem to “pop” much less these days versus the 10.5 days. Even though the pop is still there, I can live with it for now.

You might say, “Take a look in your Console log and see what is happening when your computer should be going to sleep automatically based on your energy saver preferences.” Been there, done that. The console had very little to report around what should have been the set auto sleep time.

The second system adjustment I made today was to install Apple’s latest Security Update 2010-001. The update is not large, but seems to address some significant security issues including, among other fixes/patches, a fix for openSSL:

Description: A man-in-the-middle vulnerability exists in the SSL and TLS protocols. Further information is available at http://www.phonefactor.com/sslgap A change to the renegotiation protocol is underway within the IETF. This update disables renegotiation in OpenSSL as a preventive security measure. The issue does not affect services using Secure Transport as it does not support renegotiation. Credit to Steve Dispensa and Marsh Ray of PhoneFactor, Inc. for reporting this issue.

Also a fix for CoreAudio that seems significant:

Impact: Playing a maliciously crafted mp4 audio file may lead to an unexpected application termination or arbitrary code execution

Description: A buffer overflow exists in the handling of mp4 audio files. Playing a maliciously crafted mp4 audio file may lead to an unexpected application termination or arbitrary code execution. This issue is addressed through improved bounds checking. Credit to Tobias Klein of trapkit.de for reporting this issue.

Is it possible my own systems were compromised by either of those vulnerabilities? I doubt it, but you never know. It has been said that Apple, from time to time, will quietly fix nagging software issues with innocuous and non-specific software updates such as “Security Updates.” Is this true? Who knows, either way, to recap: Installed latest security update 2010-001 & uninstalled LaunchAgent “Antipop” equals functional auto sleep on all 3 systems running 10.6.2 and a much more-functional and quiet HDD on the Dell Mini 10v running Snow Leopard 10.6.2.