Logic Pro 9 Trouble Shooting For A Friend


Hey All,

A colleague of mine is having trouble with a brand new Logic 9 installation on a brand new 12 core Mac running OS 10.6.8 and I can't quite seem to get to the bottom of it.

He is having a sort of "latency" between the metering in his AU plug-ins (either third party or native Logic) and the sound of the audio. I've had him check the obvious things; but it has been inconclusive thus far. So far he has tried the following:

* Turning all latency compensation off.

* Trying various buffer settings.

* Removing any potential latency inducing plug-ins from the main outputs.

* Running with the Mac built in audio (no difference).

* He has run the same AU plug-ins in Reaper and not had this problem.

I figured it was time to call in the collective brain trust for some brain storming. Any ideas or insights are welcome....



Hi Eli,

Are you saying that it's a graphics latency between the sound and the metering?
The actual playback sound is ok?

Version of L9? 9.1.5?
Running Logic in 32 bit or 64 bit mode?
Plug-ins 32 bi or 64?
Amount of RAM?
What does the core activity look like in Logic's CPU meter?

Maybe it's old news, but last year there were issues with 6 and 12 core Mac Pro models. I'm not sure if L9.1.5 has resolved this. I'm just trying to point to possible reasons why this strange behavior is occurring.


New Member
Thanks guys, decided to join myself lol

64bit both logic and plugins
tons of ram (24M)
barely going as far as CPU...a small session, just one plug in instanciated

Playback sounds fine, meters on logic mixer are fine, meters in MIO and on my interfaces are also fine. Plugins with metering, Logic, or AU's are all late even with all compensation disabled. Reaper and PT are fine (with their respective compatible plug-ins). Even a simple plug in with just one LED for metering is late (earreckon free87 for example) :brkwl:



New Member
Just tried the same session and Logic version on a laptop in both 32 and 64 bit modes and everything works fine so CSeye, you may be on to something.



Sometimes we overlook the most obvious things! Thanks Jay. (I swear, this forum is sometimes like a House episode - doing a differential diagnosis with colleagues:))