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Re: Crackling audio? Try CoreAudio Aggregate Devices.
Posted: Thu Aug 04, 2005 7:05 pm
by croyal
Thanks Sooshie and Qo.
I just moved up to the G5 and today started getting spikes and crackles only when auditioning soundbites in the editor. I have only one interface- but it is indeed from Apogee.
Needless to say- after creating Aggrigate device and reconfig of Audio Bundles- all works flawlessly- even with buffer at 128!!!.
Great detective work, you two!!!
Chris
Re: Crackling audio? Try CoreAudio Aggregate Devices.
Posted: Thu Aug 04, 2005 7:38 pm
by guitarbth
I'm having the same problems. I have a Firewire Solo as well. I'm trying to use this trick but after I click on Audio Devices I see no Menu to choose aggregate devices. Where is it? Thanks.
Brandon
Re: Crackling audio? Try CoreAudio Aggregate Devices.
Posted: Thu Aug 04, 2005 7:51 pm
by qo
Originally posted by Croyal:
Needless to say- after creating Aggrigate device and reconfig of Audio Bundles- all works flawlessly- even with buffer at 128!!!.
Excellent Chris! I'm so happy this is working for others. After weeks and weeks of this problem, I'm still a bit paranoid about hearing a crackle but so far (knock, knock) it's all been golden.
Originally posted by azusa:
Wow!! This is the coolest trick of the year.
Great job qo.
Thanks for that azusa! Sometimes trying totally off-the-wall insane stuff works. Not often. Just often enough to keep trying

All the other stuff I've tried that didn't work is too embarrassing to mention

Re: Crackling audio? Try CoreAudio Aggregate Devices.
Posted: Thu Aug 04, 2005 7:57 pm
by qo
Originally posted by guitarbth:
I'm having the same problems. I have a Firewire Solo as well. I'm trying to use this trick but after I click on Audio Devices I see no Menu to choose aggregate devices. Where is it? Thanks.
Hi Brandon,
It should be under the Audio menu in Audio/MIDI Setup's main menu bar (just to the right of the Apple menu). There's a keyboard shortcut for it: Shift+Apple+A
Let us know if that doesn't work, OK?
Re: Crackling audio? Try CoreAudio Aggregate Devices.
Posted: Thu Aug 04, 2005 8:40 pm
by guitarbth
Still no luck. But I think I figured it out. I'm not using Tiger which I believe is when the Aggregate Device was introduced. Correct?
Thanks.
Brandon
Re: Crackling audio? Try CoreAudio Aggregate Devices.
Posted: Thu Aug 04, 2005 9:05 pm
by Shooshie
Originally posted by guitarbth:
Still no luck. But I think I figured it out. I'm not using Tiger which I believe is when the Aggregate Device was introduced. Correct?
Thanks.
Brandon
Yes, Brandon. Unfortunately for some, this is a Tiger-only feature. I remembered that being a feature of Tiger, allowing multiple audio interfaces for all comers. That's how they did it; they created the aggregate device, which DAWs see as only one device. It's very interesting to me that Core Audio can see the interfaces, combine them, and present them to Digital Performer in a form that it is very happy with, when DP itself could not do that.
Such is technology. Thank goodness it keeps getting "better." Now you have one more reason to upgrade to Tiger.
Shooshie
Re: Crackling audio? Try CoreAudio Aggregate Devices.
Posted: Thu Aug 04, 2005 9:11 pm
by Shooshie
Originally posted by qo:
After weeks and weeks of this problem, I'm still a bit paranoid about hearing a crackle...
Don't be. That
article in Sound on Sound described this in great detail, and I am confident that we've found the Yellow Brick Road again. So, don't worry; be happy. We're off to see the wizard! (curse those flying monkeys!)
Shooshie
Re: Crackling audio? Try CoreAudio Aggregate Devices.
Posted: Fri Aug 05, 2005 8:27 am
by guitarbth
Well, even though I don't have Tiger and cant use the aggregate device trick I was able to get rid of the distortion I was experiencing by removing an instrument track that I was playing along with....
Brandon
Re: Crackling audio? Try CoreAudio Aggregate Devices.
Posted: Fri Aug 05, 2005 8:35 am
by qo
Originally posted by guitarbth:
Well, even though I don't have Tiger and cant use the aggregate device trick I was able to get rid of the distortion I was experiencing by removing an instrument track that I was playing along with....
Hi Brandon,
Yes, one thing to note is that what we are discussing is a solution to a problem that is independent of CPU utilization. The crackles occur when CPU is almost idle.
In your case, it sounds like the CPU is the issue. You can display CPU usage using Studio->Audio Performance
I still get pops if I max out the CPU in DP using VI's. But, this is expected behavior and correlates exactly with the CPU meter maxing out.
EDIT: Corrected the menu item reference above now that I'm home
<small>[ August 05, 2005, 10:04 PM: Message edited by: qo ]</small>
Re: Crackling audio? Try CoreAudio Aggregate Devices.
Posted: Fri Aug 05, 2005 1:02 pm
by thermos
Qo, you are a saint and a savior! You can really die happy given your contribution to the audio community at large. With my firefaces, the difference is huge. On a large session, I get way less dropouts, timing issues, just a lot less flinching in general. Great work!
Re: Crackling audio? Try CoreAudio Aggregate Devices.
Posted: Fri Aug 05, 2005 7:30 pm
by qo
Wow, thank you thermos! I think I now understand how Sally Fields felt at the Oscars when she said "You
do love me!"

(OK, I've just dated myself, heh).
Re: Crackling audio? Try CoreAudio Aggregate Devices.
Posted: Fri Aug 05, 2005 10:06 pm
by Gabe S.
Hi.
I used Aggregate Devices to solve the exact same click/pops as described by Qo and Shooshie. That was great.
However, I couldn't get a movie to play in DP while the Aggregate Device was the active device. As soon as I unselected the Aggregate Device and then did it the old way of selecting both devices, the problem went away.........bummer.....I started another thread with the movie problem before I realized what the "fix" was.......
Anyone else seeing this?
My interfaces are a Mobile IO and (2)x2408's.
Thanks.
-gabe
Re: Crackling audio? Try CoreAudio Aggregate Devices.
Posted: Sat Aug 06, 2005 3:09 am
by Shooshie
Oh dear. For every solution for a given problem, there exists an opposite and equal problem along the same straight line. I hope that's fixable. I'm not working with a movie at the moment. Maybe someone else will tackle it. If it's a problem, we should report it to MOTU... er... after we convince them that there was a problem beforehand, and that qo solved it!
"Moof," said the dogcow.
Shooshie
Re: Crackling audio? Try CoreAudio Aggregate Devices.
Posted: Sat Aug 06, 2005 6:34 am
by Gabe S.
I reported this crackling issue at NAMM....to a senior tech guy....he was very nice, but had never heard of the problem.
The problem didn't exist in 4.12 for me. It appeared in 4.5 and has been there ever since.
When I saw qo's post a couple weeks ago and finally upgraded to Tiger, VOILA! problem fixed. That was so great!
Then, I opened a move last night and then bang.....problems again...but this time different.....argh.....
I'm gonna call MOTU on Monday.....
Thanks.
-gabe
Re: Crackling audio? Try CoreAudio Aggregate Devices.
Posted: Sat Aug 06, 2005 4:07 pm
by melodesiac420
Well... Looks like I'll be getting Tiger tomorrow. Notime bettter than now I guess. Thanks for your help qo.