Audio stutters with USB Dacs on Macbook M1 Pro

[droid2000]

Curious issues. I’ve had zero issue with my M1 Max under any load with several devices.

Under what specific load does it occur? Is this sample rate dependent? Does it happen more often with a higher sample rate? Does it happen with all audio? Or only specifically from a single application?

I just built a new stereo system with all new audio components a couple of weeks ago. At first, I had my laptop connected directly to the DAC via USB so I could start listening right away. But when I installed the Raspberry Pi Roon endpoint, I noticed that the drops stopped. So I never got around to doing any debugging because the problem fixed itself by the time I completed the setup.

 

[Ulfgard]

Curious issues. I’ve had zero issue with my M1 Max under any load with several devices.

Under what specific load does it occur? Is this sample rate dependent? Does it happen more often with a higher sample rate? Does it happen with all audio? Or only specifically from a single application?

It happens when the ”Memory Pressure” exceeds about 66%. I don’t know what this value means exactly. The way to reproduce it is to use the system hard. I can always reproduce the issue by: Running the tool amazing.ai to generate some AI images, (re)starting PyCharm, (re)starting webbrowsers / mail app etc … Please note the system stays absolutely responsive, the fans don’t even turn on. This load should be nothing for the system. Yet, as soon as my tool shows 66% memory load the music output is ruined.

It happens with all frequencies, all sample rates, all audio, all apps. And also with all USB 2.0 DACs I’ve tried so far.

Audio output using speakers, Qudelix 5K Dac, Headphone jack, Blutooth DAC and Apple Studio Display is fine.

 

[Ulfgard]

I had the same problem with a Macbook M1 Pro with a USB connection to an RME ADI-2 DAC.
[…]

Roon sounds like an interesting tool I will check out, but that setup is not an option for me.

I like the idea of getting the audio out of the Mac via ethernet. I was also thinking about using an HDMI cable for that (M1 has a connector, so has my docking station) but I did not find a compatible headphone DAC.

 

[Axo1989]

Curious issues. I’ve had zero issue with my M1 Max under any load with several devices.

Under what specific load does it occur? Is this sample rate dependent? Does it happen more often with a higher sample rate? Does it happen with all audio? Or only specifically from a single application?

I'm using MBP 13" so vanilla M2 (just an Air with a fan basically, I bought it to keep the TouchBar for as long as possible).

But I don't associate the issue with cpu load per se. As mentioned, I usually notice the issue when Safari has upped the memory pressure without necessarily taxing the cpu. That machine has 24 GB RAM (less than I'd prefer but more than average) and I tend to accrete a lot of tabs when working or looking up catalogs (alongside general use) so it's easy to push that.

The easiest fix is to quit Safari and start again without tab detritus, so while it may not be a memory issue at all it relates to Safari's use of resources somehow. I haven't tried loading up memory with other apps specifically, and I'm not suggesting Safari use is the only way to invoke the issue, just how it usually arises in my use of that machine (the laptop isn't my main work machine).

I note @Ulfgard's mention of the 66% memory pressure metric and I'll have to check that next time.

I'm just using the Music app to stream, as I dropped Tidal a while back (and rarely slum it with Spotify, YouTube et al). But I think the OP is correct that the stutters affect all audio, it's just more irritating with music. First thing I tried was dropping the Core Audio sample rate (I usually set it to 24/192 so as not to downsample) but looks like that isn't a factor.

My guess is it's an issue with macOS and Core Audio scheduling of application-level services that arises in my particular configuration (and some others) and one or more of the audio services isn't prioritised as I'd prefer. Also note I'm using macOS 12.6 (latest is 13.2.1) so the issue may or may not persist after upgrading. I think Safari 16.0 is current though?

 

[Axo1989]

It happens when the ”Memory Pressure” exceeds about 66%. I don’t know what this value means exactly.

Fyi memory pressure replaced physical RAM use to give a better indication of performance/limitations related to memory use. When you look at Activity Monitor you can see memory used is broken down into app/wired/compressed and you can also see cached and swap. Memory used can easily exceed physical memory but macOS (and SSD hardware) is good at managing things so memory pressure takes into account how critically memory resources (actual RAM and compressed/cached/swapped) are being taxed.

 

[Zek]

I'm just using the Music app

Maybe a third party audio player can solve that problem if it is set to have priority.

 

[Axo1989]

Maybe a third party audio player can solve that problem if it is set to have priority.

Yes, that certainly crossed my mind and if the issue becomes intractable I'd go there (I've used Audirvāna previously for example). So far it resolves ok if I curtail any Safari excesses.

 

[Maginness]

I have a Macbook M1 Max and Mac Mini M2.

I use a single USB C cable to a CalDigit Thunderbolt 4 dock. From there I go USB A to a cheapo USB A hub then to a Topping E30 DAC. From the DAC over to a set of powered speakers. No audio issues at all. I use the setup for Zoom a lot and in between calls for music mostly using the native Mac Music app.

During the weekdays it's mostly my Macbook connected to the dock, it has 64gb memory and I never get much above 34gb in use.
Other times it's my Mac Mini connected to the dock and then the DAC. That has 8gb memory and sits around 6gb or higher a lot. Still no audio issues via the external DAC.

I have found variance in Apple devices. Have had two identical Macbooks before. One was awful with Bluetooth and had Wifi issues too. Apple said it passed all checks, reimaged for me and that was it. That one machine was never as reliable as the other identical Macbook. Same with iPhones. Two identical phones, one was much better with cellular connectivity, much better with Airdrop, and better with Bluetooth. Have an Intel Mac Mini that passed all of Apple's checks and to me has video quality issues and connectivity issues too.

 

[anotherhobby]

I was given an M1 MacBook Pro thru work last year, and it exhibited this very issue with EVERY single external DAC that I tried, and even using the headphone jack out (so using the built-in DAC). I tried a million things to resolve this exact specific audio drop out problem being discussed (along with constant network issues as well), but to no avial. I was never able to fix it, and after several months I finally convinced my work to give me the newest Intel based MacBook Pro they had on hand. Every single issue was immediately 100% resolved. I knew this would be the case, because my personal laptop is also the very last generation Intel based MacBook Pro, and it's flawless.

I am aware that my response is of little help to anybody suffering with the issue, but it also happens to almost everybody I work with who has an M1 also. Constant network issues and audio drop outs during zoom meetings. I can't believe Apple has not managed to fix this issue, especialy considering how much they are used in Pro Audio. All I know for now is that I hope my Intel Macs last long enough until it's solved, but as problems go, it's 100% unacceptable. It reminds me of back when Apple switched from PPC to Intel, and the exact same type of crap plagued MacOS on Intel for years.

 

[Sokel]

It's not a common problem when playing audio (more of an issue with video) but usually it's related to multitasking & interrupts. It could be another application, driver, or background process... It's usually "something else" messing-up the audio...

The operating system is always multitasking even if you are only running one application so there is a buffer. During playback the buffer gets filled in a quick burst and the audio flows-out to the DAC at a smooth-constant rate. If something hogs the system for a few milliseconds too long and the buffer doesn't get re-filled in time you get buffer underflow and a glitch. It doesn't have to be using lots of total CPU time, it just has to hog the system a little too long.

.

..When recording, there is a recording buffer that works the other way. Data flows-in smoothly and it gets written to the hard disc is a quick burst. Here the danger is buffer overflow if it doesn't get read in time.

I have deliberately try to find the "limit" of where the audio starts to have issues with my 10yo machine,so I played heavy video with MPC,play foobar with full DSP array loaded and as it still played ok I tried CPUId's bench test on top of them.The later did the trick.
I would suspect some thermal issues on Mac,maybe a good cleaning will fix it.

 

[Axo1989]

It's not a common problem when playing audio (more of an issue with video) but usually it's related to multitasking & interrupts. It could be another application, driver, or background process... It's usually "something else" messing-up the audio...

The operating system is always multitasking even if you are only running one application so there is a buffer. During playback the buffer gets filled in a quick burst and the audio flows-out to the DAC at a smooth-constant rate. If something hogs the system for a few milliseconds too long and the buffer doesn't get re-filled in time you get buffer underflow and a glitch. It doesn't have to be using lots of total CPU time, it just has to hog the system a little too long.

I have deliberately try to find the "limit" of where the audio starts to have issues with my 10yo machine,so I played heavy video with MPC,play foobar with full DSP array loaded and as it still played ok I tried CPUId's bench test on top of them.The later did the trick.
I would suspect some thermal issues on Mac,maybe a good cleaning will fix it.

I think @DVDdoug is more on the money here. I'm not having cpu load or heat/throttling issues. And my Mac is too new to be haunted by dust bunnies. The OP's isn't so old either.

 

[Sokel]

The OP's isn't so old either.

It doesn't need to be old,6 good months of dust can do the damage just fine.
It depends of course,on summer with wide open houses dust is easier to sneak in.
I usually clean mine once every coulpe of months and the dust is no negligible even with my mania for clean house.
Of course @DVDdoug is more on the money,no doubt about it.

 

[anotherhobby]

I think @DVDdoug is more on the money here. I'm not having cpu load or heat/throttling issues. And my Mac is too new to be haunted by dust bunnies. The OP's isn't so old either.

When considering my above work computer example, this could be the case for my situation as well since me and all of my coworkers have the same overly agressive security scanning crap running under the hood.

 

[Axo1989]

It doesn't need to be old,6 good months of dust can do the damage just fine.
It depends of course,on summer with wide open houses dust is easier to sneak in.
I usually clean mine once every coulpe of months and the dust is no negligible even with my mania for clean house.

That's true. My place (and thus home office) needs constant cleaning and I'm often amazed by the intricate buildup on intake vents &etc.

 

[Ulfgard]

I'm using MBP 13" so vanilla M2 (just an Air with a fan basically, I bought it to keep the TouchBar for as long as possible).

But I don't associate the issue with cpu load per se. As mentioned, I usually notice the issue when Safari has upped the memory pressure without necessarily taxing the cpu. That machine has 24 GB RAM (less than I'd prefer but more than average) and I tend to accrete a lot of tabs when working or looking up catalogs (alongside general use) so it's easy to push that.

The easiest fix is to quit Safari and start again without tab detritus, so while it may not be a memory issue at all it relates to Safari's use of resources somehow. I haven't tried loading up memory with other apps specifically, and I'm not suggesting Safari use is the only way to invoke the issue, just how it usually arises in my use of that machine (the laptop isn't my main work machine).

I note @Ulfgard's mention of the 66% memory pressure metric and I'll have to check that next time.

I'm just using the Music app to stream, as I dropped Tidal a while back (and rarely slum it with Spotify, YouTube et al). But I think the OP is correct that the stutters affect all audio, it's just more irritating with music. First thing I tried was dropping the Core Audio sample rate (I usually set it to 24/192 so as not to downsample) but looks like that isn't a factor.

My guess is it's an issue with macOS and Core Audio scheduling of application-level services that arises in my particular configuration (and some others) and one or more of the audio services isn't prioritised as I'd prefer. Also note I'm using macOS 12.6 (latest is 13.2.1) so the issue may or may not persist after upgrading. I think Safari 16.0 is current though?

The issue is not related to what other apps are running. I'm not using Safari - I think that browser is just good at utilizing the system to the max, that's why you notice issues.

With macOS Ventura version 13.2.1 (22D68, the newest one from this week) the stutters happen less often. The changelogs don't mention anything about audio improvements, though.

 

[Ulfgard]

Here is another update to further document my odyssey journey:

The Sabaj A20D also stutters, even though this DAC has a USB-C connector and is listed as USB 3.1 device (just like my working Qudelix).

I'm wondering if my audio stuttering is jittering due to an unknown hardware issue with the Mac's USB port. I now ordered some USB cleaners / anti-jittering devices, even though they are not reviewed positively here.

 

[anotherhobby]

Here is another update to further document my odyssey journey:

The Sabaj A20D also stutters, even though this DAC has a USB-C connector and is listed as USB 3.1 device (just like my working Qudelix).

I'm wondering if my audio stuttering is jittering due to an unknown hardware issue with the Mac's USB port. I now ordered some USB cleaners / anti-jittering devices, even though they are not reviewed positively here.

Have you tested the headphone jack? Try that for a while. When I had my M1, the headphone jack was not immune to this issue.

 

[Ulfgard]

Have you tested the headphone jack? Try that for a while. When I had my M1, the headphone jack was not immune to this issue.

I have no issues with it.

 

[Axo1989]

The issue is not related to what other apps are running. I'm not using Safari - I think that browser is just good at utilizing the system to the max, that's why you notice issues.

Agree, that's just the most common way I generate a lot of memory pressure on that laptop (my desktop has more memory and would more likely be pressured by the GIS app, but it's an Intel model—albeit with the T2 and its audio controller—and the issue hasn't really come up).

With macOS Ventura version 13.2.1 (22D68, the newest one from this week) the stutters happen less often. The changelogs don't mention anything about audio improvements, though.

That's somewhat promising.

 

[Phonima]

Hi @Ulfgard, I have a 16" 2021 MacBook Pro M1 Pro (macOS 12.6.3), a Chord Mojo 1 and a Zen DAC v2 and I have the identical issue using both the DACs.

I'm streaming Apple Music from my iPhone 13 Mini without any sound issue now. My older MacBook Pro 2014 has no sound issues.

Solution 2 (deleting audio plist files) in this video seems to be be temporary fix.