Re: Coreaudio-api Digest, Vol 4, Issue 93

Subject: Re: Coreaudio-api Digest, Vol 4, Issue 93

From: Dominic Feira <email@hidden>

Date: Fri, 30 Mar 2007 16:41:24 -0400

Delivered-to: email@hidden

On Mar 30, 2007, at 15:04, email@hidden wrote:

* Summary of Problem:

   When playing multiple audio files, a user reports drop-outs

lasting from ~0.1 to ~1 second, usually around ~.5. The dropouts

manifest across all files and all output channels simultaneously.

* Hardware / OS / file specs:

   Dual 2.7GHz G5 with 4G RAM

   OS 10.4.8 and 10.4.9 (Drive wiped clean, reinstalled OS to ensure

clean system.)

<snip>

   When trying to recreate a similar system to test first-hand, I used:

   1.25 GHz PowerPC G4 (1 CPU), 1 GB RAM (PowerBook)

   Firewire MOTU UltraLight

   Strangely, I am getting no dropouts on my less powerful machine.

One thing to keep in mind with the G4s, is that their clock speed isn't skewed like a G5. It is always 1.25GHz. As I understand it the adjustment of clock speed on the G5 (which you can't disable) can take a relatively long time to occur. Real-time apps sometimes run "better" on G4s because of this. I'm sure the core audio guys can fill you in on this as they have to deal with it for their predictive audio callback scheduler.

This might not be part of your problem at all. I just thought I'd mention it.

Dominic Feira / Code Monkey / Ambrosia Software, Inc. -- http://www.AmbrosiaSW.com

_______________________________________________ Do not post admin requests to the list. They will be ignored. Coreaudio-api mailing list (email@hidden) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/coreaudio-api/email@hidden This email sent to email@hidden

Follow-Ups:

Re: Coreaudio-api Digest, Vol 4, Issue 93
- From: Jeff Moore <email@hidden>
Re: Large matrix mixers
- From: Christopher Ashworth <email@hidden>