Cracking sound with late-2013 MBP

[Undertones]

Me and a few others over at Gearslutz are having issues with the latest iMacs and Macbook Pros.

There seems to be one issue related to fusion drives, and another related to playing back audio using 256 or lower buffer sizes. The latter gives crackling audio no matter what, especially on 64 and 32 samples. This is the issue I'm experiencing.

My rig is a brand new late-2013 15" MBP with a 256gig SSD, Mavericks and PT 10.3.7. Using UAD Apollo with the Thunderbolt card as well.

The issue seems to be gone if I'm using PT11.02, but it could be because I'm testing with different sessions.

Anyone from Avid know if Apple are aware of this? Can we get some info?

[Chief Technician]

Which version of Mac OS?

[Undertones]

Originally Posted by chief technician

which version of mac os?

os x 10.9 (13a3017)

[Darryl Ramm]

You do realize that Pro Tools is not yet officially supported in Mavericks. That does not mean it won't work, folks are using it. And hopefully you are aware of the known issues. I don't think UAD support Mavericks yet either, with Apollo drivers or UAD plugins.

Start at the "Help us help you..." link above.

And you have a dedicated audio spec drive for session/audio files?

What exactly are all the drives (make/model/spec) connected or in the Mac and what are they used for? e.g boot/system, audio/session files, VI sample files?

What exactly are you recording from what sources? Session sample rate?

What are all the Pro Tools playback engine settings? If ignore errors is checked, try unchecking it and seeing if Pro Tools throws an error.

What standard troubleshooting steps have you tried? Has the system been properly optimized for Pro Tools?

And what plugins are being used in these sessions with problems and exactly how if they are UAD plugins, running in Pro Tools or in the console while tracking. If in Pro Tools then this may be running totally as expected, UAD plugins (in Pro Tools) have high latency to the DSP and not intended for use at small buffer sizes, especially bad for the very high latency USD resampling plugins. Lots if info in the USD documentation on all this.

[Undertones]

I'm using the exact same setup on my 2011 MBP, and everything is working there. I'm gonna try reverting to Mountain Lion to see if that helps.

The only thing that's changed is the Mac itself. Lots of other people are having this issue as well. Here's the Gearslutz thread:

http://www.gearslutz.com/board/music...new-imacs.html

I get a 6101 error if I disable the error supression. Strange, since I'm barely hitting 20% CPU at the most.

[Darryl Ramm]

Downgrading the OS might help, but it may be a lot less work if you just answered the other questions first.

The link to yet more rambling on Gearslutz does not help at all. These may all be unrelated and this type of problems is very common and can have several very common causes (improper clocking with digital sources, lack of a dedicated audio drive, too small a buffer size with PT hosted UAD plugins, lack of optimization-especially not disabling spotlight indexing and a few others, various file corruption etc etc.). Start by explaining exactly the setup you have and exactly what is in the session, what standard troubleshooting and optimization steps you have tried and answer the other questions.

6101 error with Pro Tools hosted UAD plugin? With a small IO buffer. That may just be working as expected... if you compare to Pro Tools 11 you cannot have any plugins hosted in Pro Tools/AAX-64 is that the difference between session? If so that is a very obvious suspect.

[Darryl Ramm]

And although far from the top of my list of things to check, if everything else is properly configured and optimized I would try disabling Mavericks' App Nap for Pro Tools and the UAD console and anything else possibly related. But again the lack if lots if clear detailed info here is not helping.

[Chief Technician]

Originally Posted by Darryl Ramm

The link to yet more rambling on Gearslutz does not help at all. These may all be unrelated and this type of problems is very common and can have several very common causes (improper clocking with digital sources, lack of a dedicated audio drive, too small a buffer size with PT hosted UAD plugins, lack of optimization-especially not disabling spotlight indexing and a few others, various file corruption etc etc.)

I know of a few colleagues who are finding issues with UAD plug-ins and v11. Neither one of them is using Mavericks.

[Darryl Ramm]

Originally Posted by Chief Technician

I know of a few colleagues who are finding issues with UAD plug-ins and v11. Neither one of them is using Mavericks.

Finding issues? Besides UAD not having AAX-64/Pro Tools 11 support at all? :-O

You mean issues even when running the plugins within the UAD Console only?

It would kinda be nice if there was a clear description about what was going on here with this problem.

[Chief Technician]

Originally Posted by Darryl Ramm

It would kinda be nice if there was a clear description about what was going on here with this problem.

The progression of this thread leads me to believe there is a hardware compatibility issue between the late 2013 MBP and the UAD hardware. I suggest you open a dialog with UAD if you have not already done so.