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Sound stuttering after Mountain Lion install

Dear community,


after having installed OSX Mountain Lion my sound startet stuttering whenever there is rapid movement on my screen.

This includes e.g. window movement, scrolling through image loaded websites or video playback (flash player, quicktime).

A restart didn't help. I'm using stereo output, not digital.


I have connected a second monitor but the problem persists after disconnecting it. Movement on the second monitor also causes the sound to stutter.

My GPU Diode temperature is at 85°C (there is some bug that keeps the GPU under load while a second monitor is connected AFAIK), but I guess it was the same under Snow Leopard.


In Snow Leopard the sound output was always perfect even under heavy load or heavy HDD I/O.


Any ideas?

iMac (27-inch Mid 2011), OS X Mountain Lion

Posted on Jul 28, 2012 5:48 AM

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Question marked as Top-ranking reply

Posted on Jul 28, 2012 3:22 PM

I am also having this issue as well.


I opened Activity Monitor and noticed that during the stuttering, coreaudiod jumps in CPU usage, often past 5%. I have also noticed graphics lag when this occurs if I'm doing something like watching full-screen video or gaming.


I'm currently experiencing this on mid 2011 iMac 27" as well as a 24" iMac 2009 model I use at work.

1,223 replies

Nov 7, 2012 2:36 PM in response to MoogNinja

I jumped from SL to ML too. SL was rock solid, but I do like ML aside from this issue.


The problem seems so random and intermittent. I reset my PRAM 3 times the other day and it seemed to sort things out, certainly no more kernel panics. 3-4 days later and seemingly no issue with tunes playing all day, then suddenly I had a very slight stutter today, then nothing again. I know the mdworker has issues, I wonder if that has anything to do with this.


I tested using my MBA playing tunes for a day and had no issue, which is why I was starting to thing my iMac may have some hardware issue, although it's totally fine in regards to gereral performance. The more reports I read on here point to it surely being a OS issue, especially if the issue has stuck since Lion as ML is predominately the same OS with additional features.


I would happily install some diagnostic software if Apple would get in touch.

Nov 7, 2012 2:52 PM in response to MoogNinja

Yes this concerns me greatly. They moved ahead after the Lion issues and now I see on TUAW that there is an OS X 10.9 about.

Seriously?!

Have any of you tried to find this specific thread on here by typing "sound stuttering after" ? There are dozens of them!

This is just madness. How are we supposed to work like this?

Today I got video flickering while playing an AVI file and copying 120 gigs of data to the same drive.

Nov 9, 2012 8:18 AM in response to tttxx

Just had the issue again, here's the console log from the exact time the issue occured - my hunch may be right, the dreaded mdworker seems to have caused this one...


09/11/2012 16:03:55.000 kernel[0]: Sandbox: sandboxd(53177) deny mach-lookup com.apple.coresymbolicationd

09/11/2012 16:06:19.000 kernel[0]: IOAudioStream[0xffffff802ae9ea00]::clipIfNecessary() - Error: attempting to clip to a position more than one buffer ahead of last clip position (46d2,1f0)->(46d3,30c).

09/11/2012 16:06:19.000 kernel[0]: IOAudioStream[0xffffff802ae9ea00]::clipIfNecessary() - adjusting clipped position to (46d3,1f0)

09/11/2012 16:06:19.000 kernel[0]: IOAudioStream[0xffffff802ae9ea00]::clipIfNecessary() - Error: attempting to clip to a position more than one buffer ahead of last clip position (46d4,1b0c)->(46d5,2c74).

09/11/2012 16:06:19.000 kernel[0]: IOAudioStream[0xffffff802ae9ea00]::clipIfNecessary() - adjusting clipped position to (46d5,1b0c)

09/11/2012 16:06:20.839 mdworker[53259]: Unable to talk to lsboxd

09/11/2012 16:06:20.877 mdworker[53260]: Unable to talk to lsboxd

09/11/2012 16:06:20.898 sandboxd[53261]: ([53259]) mdworker(53259) deny mach-lookup com.apple.ls.boxd

09/11/2012 16:06:20.902 sandboxd[53261]: ([53260]) mdworker(53260) deny mach-lookup com.apple.ls.boxd

09/11/2012 16:06:21.000 kernel[0]: Sandbox: sandboxd(53261) deny mach-lookup com.apple.coresymbolicationd

Nov 9, 2012 9:02 AM in response to designaholic

I think I have something similar here, too:


Nov 9 17:56:10 frederiks-imac.speedport.ip mdworker[1764]: Unable to talk to lsboxd

Nov 9 17:56:10 frederiks-imac.speedport.ip mdworker[1763]: Unable to talk to lsboxd

Nov 9 17:56:10 frederiks-imac.speedport.ip sandboxd[1765] ([1764]): mdworker(1764) deny mach-lookup com.apple.ls.boxd

Nov 9 17:56:10 frederiks-imac.speedport.ip sandboxd[1765] ([1763]): mdworker(1763) deny mach-lookup com.apple.ls.boxd

Nov 9 17:56:11 frederiks-imac kernel[0]: Sandbox: sandboxd(1765) deny mach-lookup com.apple.coresymbolicationd


but what is "mdworker"?^^


Edit: ok google says "mdworker" is spotlight which is indexing new files…so should I try to turn off spotlight?

Nov 9, 2012 12:03 PM in response to ElisabethR

Same problem here. Unfortunatley, I'm running a new Macbook Pro (non-retina), so I can't "downgrade" to SL (otherwise I'd do it in a heartbeat).


I installed the Macbook Pro update 2.0 last night, but haven't seen any improvement... I was hoping that might address this issue... I was interested to see FrederikY's post, which at least includes a specific reference to audio. Looking around, I found this mentioned on the coreaudio-api mailing list:


"I have never known this log message to be indicative of an IO problem. In fact, it is more likely that the app experiencing the glitch had it's problem first. Then, after the HAL resynchronized as part of recovering from the glitch, it triggered this log message when it resumed calling the kernel trap."


This was in response to a developer who noticed the same error correlated with audio drop-outs in his app. The thread was from 2010, which suggests that it wasn't strictly Lion or ML related... However, I suppose it may be related to a similar underying problem. Dunno.

Nov 9, 2012 7:26 PM in response to tttxx

I emailed my contact guy from when they reached out for the engineers about polling our system for reports 6 weeks ago or so. He replied that he still didn't have an update. I'm honestly at the point that I just want them to replace both of my computers. If they can't make software with their own hardware then that's just bad business and completely unacceptable. I'm going to give them the chance to capture my two units and supply two new ones with newer hardware that hopefully are supported by their own OS. If I can't get that, I'm just going to let a judge decide what the best course of action is. I spoke to one rep on the phone today who was rude as can be and said I could pay them for tech support and trouble shooting my computer. Even in the face of it being their fault they wanted to extort more money out of me. Now that is rubbish.

Nov 9, 2012 7:49 PM in response to BarrettF77

This has gone beyond the point of anything reasonable! I have yet to hear back from my initial problem and I reported that shortly after Mountain Lion became available!

All I have to do is look at the Feedback on the App store and see all the negative reviews, including more than enough reports of sound problems and Battery problems!

Why hasn't Apple acknowledged ANYTHING about this? I'm holding on to a not very stable clone of a Lion install from months back simply because I can listen to iTunes, watch a movie, play Starcraft all without problems!

I have about 1.5 years left on the Apple Care for my 27" i7 iMac, and I'm considering installing Mountain Lion again just so I can take it to Genius and show them what we are going through! That and the bleedthrough I get on the lower left hand corner of my screen have made me turn a corner in my Apple support!

My next machine might simply be a discounted Windows 7 machine by Dell or HP, simply because I know they give support When It Counts!

Also I've not found anywhere on the App store that could help me get my Money back for my Purchase of Mountain Lion! Since it Does Not WORK I think I deserve my money back!

Is this really going to be any better with the new OS X? or will it run great for the first hour simply because it had a restart?

I should not have problems with this machine! An iMac i7 core, 2GB video card, 1 TB hard drive, it should be top of the line, instead i paid for a Mercedes and wound up with a Ford!

Nov 9, 2012 8:13 PM in response to tttxx

Mark, the only good thing I have to say about Apple is they gave me my money back FAST! Like over the top nicey nicey to me in email (probably cause I yelled so loud here). Just email customer service and say you need to use sound for your work, sound is disfunctional, thus you need money back.


For people in pro audio using a Metric Halo interface; MH came out with a work around driver this week. I made a TM backup of my solid SL system and ventured to ML again using the new driver. The pops went WAY down but still a few. I restarted and it was pop free for the rest of the night. I'll report back after this weekend of recording but it was clean this morning too so fingers crossed.


But this tells me a third party already figured out what Apples problem is and made a fix? Maybe Apple should be communicating with people!!!

Nov 10, 2012 9:45 AM in response to MoogNinja

Well, I just got passed up to customer relations where they told me my 2010 and 2011 iMacs are too old to refund. So I'm not sure how you managed that, but they don't want to do it voluntarily. I'm giving them one last chance to get in touch with the engineering team so that I can again document I've gone above and beyond to let them resolve this issue before my hand is forced.


If they marketed these machines as gaming consoles and were used for leisurely activities, that would be one thing. It's entirely another when you need it for work and they market them for creative business professionals.

Sound stuttering after Mountain Lion install

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