Logic Pro X Sudden Audio Big Latency Bug

Hello, I use Logic Pro X (latest version) on Macbook Pro Retina 15 (latest OS X) with Motu Microbook 2 sound card. Sometimes strange and disturbing bug happens.

I playing on my guitar WITHOUT any plugins or tracks with 128 I/O buffer size. During the recording audio or just playing with input monitoring, in some moment of time sound cracks and start playing with big latency (about 0.5 - 1 sec). And nothing can fix it, except unchecking Core Audio checkbox in preferences and return it back. So, again:

- I not use any plugins at all.

- There may be only one audio track in the project.

- Recording delay set at 0.

- Motu microbook direct monitoring playing normal. Only sound from Logic playing with latency.

- It happens unpredictable and nothing can fix it except restarting Core Audio.

Do you have any other applications running, and if so, which?

I quit all applications, reboot and turn off wi-fi - it doesn't help a lot, sometimes big latency suddenly appears anyway. I don't think, it depends on applications. Of course, most of the time I got Chrome and wi-fi running, and some basic like Finder of iTunes, but that's all. A few weeks ago I completely format my Macbook and install clean Yosemite with no applications and files. So now, there is only Logic, some plugins, Chrome and few other applications, that I use rarely. And like I said, closing doesn't help a lot.

and nothing can fix it, except unchecking Core Audio checkbox in preferences and return it back.

 

This is most certainly a driver issue.

I would contact MOTU about it and see what they have to say.

Not a driver issue to my experience. It's a thing i have seen since mavericks. On my studio rig, which has a tc soundcard, this happens too. And on my live rig which uses the core audio driver through a presonus soundcard we got it while playing backing tracks and guitars through an amp sim. One of the guys in my band is a unix nerd and he found a little obscure error message while digging around in sys logs. We googled the error message and got hits from people experiencing the same thing. The only thing that could make our live rig stable was downgrading to Mountain Lion. We haven't had one breakup+added latency since. On the live rig. It is a systemwide thing that was introduced in Mavericks.

Is the error message anything like this:

26/04/15 16:04:32,000 kernel[0]: IOAudioStream[0xffffff800b05f200]::clipIfNecessary() - Error: attempting to clip to a position more than one buffer ahead of last clip position (4712,24c)->(4713,456).

26/04/15 16:04:32,000 kernel[0]: IOAudioStream[0xffffff800b05f200]::clipIfNecessary() - adjusting clipped position to (4713,24c)

Because not long (two hours) after I replied to this I got the same issue: I was recording vocals, when there was a stuttering static (as if there was the infamous sample rate mismatch), and when the stutter cleared up there was this half a second latency, making recording impossible and leading to the above message in Console.

I encounter it from time to time - my "best " remedy thus far (apart from restarting coreaudio) is to bounce any and all synth- and samplertracks to audio (or freeze them), since I am pretty convinced that either a 3rd party synth or a 3rd party effect (or an as yet unknown combination of those) is causing this, or at least somehow involved. Also, other open programs using system audio are suspects: Webbrowsers, musicplayers, videoplayers, any app that uses audio really. Avoid having any of those running if possible.

To my recollection this already started in Lion (OS 10.7), but it might also be linked to one or more 3rd party plugins. One of my suspects is the Ambience plugin, a free reverb that sounds too nice to ditch. But Kontakt is also a suspect, as are some of my Rob Papen and Linplug synths.

The problem with this is that, as far as I can tell, there's no recipe to replicate it, and the Console message really doesn't tell me anything. Also, I was unsure whether it was my Hackintosh that could be the cause, but I don't think that any longer.

Is the error message anything like this:

26/04/15 16:04:32,000 kernel[0]: IOAudioStream[0xffffff800b05f200]::clipIfNecessary() - Error: attempting to clip to a position more than one buffer ahead of last clip position (4712,24c)->(4713,456).

26/04/15 16:04:32,000 kernel[0]: IOAudioStream[0xffffff800b05f200]::clipIfNecessary() - adjusting clipped position to (4713,24c)

Because not long (two hours) after I replied to this I got the same issue: I was recording vocals, when there was a stuttering static (as if there was the infamous sample rate mismatch), and when the stutter cleared up there was this half a second latency, making recording impossible and leading to the above message in Console.

I encounter it from time to time - my "best " remedy thus far (apart from restarting coreaudio) is to bounce any and all synth- and samplertracks to audio (or freeze them), since I am pretty convinced that either a 3rd party synth or a 3rd party effect (or an as yet unknown combination of those) is causing this, or at least somehow involved. Also, other open programs using system audio are suspects: Webbrowsers, musicplayers, videoplayers, any app that uses audio really. Avoid having any of those running if possible.

To my recollection this already started in Lion (OS 10.7), but it might also be linked to one or more 3rd party plugins. One of my suspects is the Ambience plugin, a free reverb that sounds too nice to ditch. But Kontakt is also a suspect, as are some of my Rob Papen and Linplug synths.

The problem with this is that, as far as I can tell, there's no recipe to replicate it, and the Console message really doesn't tell me anything. Also, I was unsure whether it was my Hackintosh that could be the cause, but I don't think that any longer.

 

That one is fairly common actually. We had those too. If you google it you will find a lot of hits from the last 5 or six years. I can't for the life of me remember what the improtant error message was but it wasn't that one. Our band unix nerd was able to dig deeper and we found the root of it. But it's a year ago now.....

 

And yes it was totally random here. It could happen at the start, middle or end of the session. But never at the same place twice. I still have the issue on my Mavericks studio system. On our downgraded Mountain Lion runs without any hickups.

 

Btw we only have one non Logic plugin running. A line 6 amp sim. And people have reported this problem with a lot of software that can play audio. Not just Logic. Suddenly the audio will break up. Come to a halt, and in some case play on after a second or so. Sometimes sounding like the wordclock is compromised.

The problem still remains. Here is the fact - it is NOT Microbook driver issue. First of all - direct monitoring from soundcard works nice with no delay. Sounds thru Logic Software monitoring and thru Motu direct monitoring not playing at same time. Second: when i got this bug again, I turn on software monitoring from Adobe Audition (with guitar effects) at the same time. And guess what? Logic and Audition was out of sync. Audition plays in sync with Motu Microbook, and Logic has latency about quarter of second.

By the way, when this bug appears, CPU peaks wasn't high. It just appears out of nowhere with short sound crack. So my conclusion is - it is definitely Logic Pro X bug. And I really don't know, what to do with it.

Ive had the same thing, disconnect and reconnect the usb cable of the audio interface and it was fixed.

Ive had the same thing, disconnect and reconnect the usb cable of the audio interface and it was fixed.

 

Just restarting coreaudio suffices. Replugging will force that, that's why it also works, but it's overkill and may wear down the hardware (oldskool aversion to hotplugging). Also, the issue is not that it cannot be "corrected", the issue is that it happens in the first place.

Thank you for advice, but unfortunately restarting it is not a solution. I trying to use Logic for live monitoring and recording at the live performance. And stability is critial for this purpose.

I have what appears to be exactly the same problem with my rig. I thought it was something to do with the roland quad capture i use as an interface. Clearly the problem is more widespread. Since my lap top is only a week old i am not that keen to downgrade the version of OSX. I'm on Yosemite 10.10.2 . Ive been trying all the different buffer settings for the quad capture. I'll let you know if any of these settings stabilize the system. If anyone has any more ideas or suggestions it would be great to hear more. Thanks

I also altered the buffer setting of my interface, to the lowest possible (48 samples) and the error has not happened since. And I have less latency.

That's great Erik!

Is Diva working fine now too?

Yes, Diva's fine, and should be, it is a gorgeous synth. I'm an Urs Heckmann-fan.

Because that clip error also happened in a project without Diva, I took it off the suspects list.

 

I actually never before touched the settings in the very "Spartan" UA-4FX system preference panel, the buffer slider has always been at the center position, which I yesterday calculated (using Logics' latency report in the prefs) to be 180 samples, added to Logics' buffer. So in reality I recorded most things with a 308 or even 436 samples buffer.

The smallest setting is 48 samples, and surprisingly, in conjunction with a smaller Logic buffer (64 or even 32) this appears to work better/more reliably than the larger buffer.

 

(For any other owner of this interface: the 5 settings on the prefpanel from Min to middle are 48, 80, 92, 168 and 180 samples. The highest setting is 665 samples. For use with Logic, go for the lowest setting that is still crackle-free.)

That's great news Erik.

Thanks for sharing.

So guys, here is update about this topic. I have changed my audio device from Motu Microbook II to Roland Octa-Capture. This is way more serious device than Microbook in my opinion. But guess what? Problem still remains the same. After hour or few there is sound crack and huge latency, that never dissapear. So it is NOT depends on sound card, or driver. It is Logic or Core Audio behaviour.

But I have found one solution. It is here:

https://discussions.apple.com/thread/6144983?start=30&tstart=0

 

They say, that problem is something about "clock" or "synchronizing external device and built-in Core Audio". So all you need to do is create Aggregate Device in Midi/Audio Settings, and combine Built-in and Roland Octa-Capture, in my case. Set Roland Octa-Capture as master clock and it will work solid and synchronized. I tried this - and this actually works, problem has gone.

 

But there is bad side of this solution. If you combine together built-in and external sound device, you'll get built-in latency. My built-in latency is something about 15ms vs Roland's 0.7-4ms. And Aggregate Device has 15 ms latency - that means that Roland Octa-Capture's power is totally worthless. Offensively.

Maybe Aggregate Device is not the best solution. Do you know something about synchronizing, clock, master/slave and all that stuff? Or at least, how to lower built-in latency as much as possible.

Creating aggregate devices will not reduce latency.

 

Did you update to 10.10.3?

Creating aggregate devices will not reduce latency.

 

Did you update to 10.10.3?

 

What do you mean "will not reduce latency"? As I said, it increased constant latency (15 ms), but took away sudden huge latency, which this topic about. Now I am thinking, how can I decrease this 15 ms as low as possible

About update - Yes I did

It's usually about the drivers involved in audio interfaces, so creating aggregate device will increase latency.

 

If you only use the Roland, how much latency do you have at a 128 or 64 buffer?

It's about 4-7 ms output latency vs 15-20 ms of Core Audio on same buffer settings

It's about 4-7 ms output latency vs 15-20 ms of Core Audio on same buffer settings

 

Did you have the same latency values with the Microbook?

Something about it, I really don't remember right now, and does it matter? it is much lower, than Core Audio anyway

Interfaces are as good as their drivers.

 

The Microbook is a simple interface, but has good drivers.

Does the Roland have its' own System Pref panel? In that, there may be a buffer setting that is added to the Logic buffer. I found out that keeping this added buffer as small as possible will decrease the occurance of those sudden buffer shifts (for me from about once every 30 minutes to about once every 24 hours). I do think now that this bug is related to the native Mac OS audio drivers, since the bug does not happen when using interfaces that have completely independent drivers (like RME).

 

In the app Console under All Messages you will probably find the following messages right after you've experienced the latency shift:

26/04/15 16:04:32,000 kernel[0]: IOAudioStream[0xffffff800b05f200]::clipIfNecessary() - Error: attempting to clip to a position more than one buffer ahead of last clip position (4712,24c)->(4713,456).

26/04/15 16:04:32,000 kernel[0]: IOAudioStream[0xffffff800b05f200]::clipIfNecessary() - adjusting clipped position to (4713,24c)

posting.php?mode=reply&f=1&t=116543#pr598186

The second message implies it is not a bug, but intended behaviour. The other day this also happened when I was watching a YouTube video (with no other open applications). I heard that familiar short stutter-crackle and immediately checked Console and found the above message again. Apart from the short hiccup there was no further issue: when only playing back sound you don't (can't) notice this added latency at all.

It is a significant issue for Logic though, and perhaps other DAW users.

I wonder if this also happens in Cubase, DP etc? Since I now know that this can happen from any app that plays audio, this would make sense. It would also be even more evidence pointing to an OS problem, rather than an application problem.

Later I will test if creating a dummy AggDev (containing just one interfaces' I/O's) somehow prevents this error from happening, though I'm sceptical.

The most annoying property of this issue is that there's no known method to reliably cause it; it's a waiting game. I now (in spite of my earlier "it's gone!" reports) still encounter this error, but only once or twice every 24 hours, where it used to be at least twice an hour.

So all you need to do is create Aggregate Device in Midi/Audio Settings

 

That's great. I'm glad you found a workaround.

Like you have noticed there are a some downsides to this method.

 

This also reaffirms my suspicion that there it has something to do with the generic USB I/O extension.

 

So it is NOT depends on sound card, or driver. It is Logic or Core Audio behaviour.

It isn't a Logic issue. It happens on other DAWs too, Apple and non Apple:

 

Unexpected Latency Issues with Mainstage

Audio Stutter/Distortion - IOAudioStream Error in Console Log | NI Support Forum

 

Something about it, I really don't remember right now, and does it matter? it is much lower, than Core Audio anyway

 

Core audio is an umbrella naming for the audio frameworks in Apple's current operating systems.

Logic can not work without Core Audio.

I test this problem last night with Guitar Rig. Just activate Octa-Capture, send music in it, open Guitar Rig with some effects, and left for 4 hours, while sleep) And at the morning there was this shift again.

Ironic thing is that Apple positioned Mac OS as most stable and easy system for music and live performances, but my old 8-years PC with Windows, Core 2 DUO, 4 GB RAM and pile of none-music stuff like games, graphic software, skype, messengers, viruses (I guess) and other garbage - works way more BETTER then Macbook Pro early 2013. More stable from ASIO and less latency. It has some audio cracles, which is normal for such old system, but it NEVER do permanent shift like that.

I guess, it was started from Maverics - Yosemite updates, because all reports on the forums dates 2012-2014 years.

This s#!+ is at least TWO YEARS old, and I guess nobody cares in Apple. F***ing morans just continue plays with their fonts and colors... I'm sorry. I'm very patient guy, but that just pisses me off.

So... I got rithorical question - will Apple fix it someday? Does anyone know any inside information?)

P.S. About Aggregate Device - this is actually the solution, I guess, but it is more like workaround or sort of hack... and again, I am not impressed about latency of that aggregate. On my old PC I can set up 3.7 ms output latency with almost no artefacts just using ASIO driver.

It's about 4-7 ms output latency vs 15-20 ms of Core Audio on same buffer settings

 

Did you read this ?

http://www.logicprohelp.com/forum/viewtopic.php?t=117043&p=600395

seems as you can reduce latency by connecting headphones to your MBP...

It's about 4-7 ms output latency vs 15-20 ms of Core Audio on same buffer settings

 

Did you read this ?

http://www.logicprohelp.com/forum/viewtopic.php?t=117043&p=600395

seems as you can reduce latency by connecting headphones to your MBP...

 

WOW Man! Thank you SO MUCH! It's actually works!

 

So in 2013 Macbooks you'll need plug in headphones to decrease latency in half. Great. It's so OBVIOUS, how can I never had guess about it? I love Apple.

WOW Man! Thank you SO MUCH! It's actually works!

 

So in 2013 Macbooks you'll need plug in headphones to decrease latency in half. Great. It's so OBVIOUS, how can I never had guess about it? I love Apple.

 

So does the workaround with the aggregate device seem to work, i.e. no sudden latency since change ?