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Ted L. Nancy · Dec 18, 2009, 03:38 PM

I have two sets of speakers that I use with my Mac Pro. The first set is a pair of Edirols that I like for DVDs and iTunes. The second is a Logitech Audiohub that I keep under my screen for YouTube, flash, and other sounds.

I know how to change the output device in System Preferences, but is there a way to setup my iTunes and DVD Player to use the Edirols and every other app to use the Logitechs?

Cold Warrior · Dec 19, 2009, 07:01 PM

open dvd player app, preferences, disc setup, and choose your preferred audio output. That should set it for the dvd player.

Not seeing any way to set it for iTunes.

Ted L. Nancy · 09:15 PM

Ok, I just tried to set that up so that my output in the Sound pane in System Preferences was set to the Audiohub (connected via USB) and the DVD Player was set to the Edirols (connected via Digital Output), but it seems I have a problem...

As soon as I started playing a DVD, a terrible loud noise that sounded like a fast machine gun or jack hammer (i.e. static) came from my Edirols.

I opened up the Audio MIDI Setup app in the Utilities folder. Now this is interesting.. the default settings for my Built-in Digital Output are 44100.0 Hz and 2ch-24bit. Under these settings as test of each speaker yields good results. HOWEVER, when I start playing a movie in DVD Player, the setting in the Audio MIDI Setup app change to 48000 Hz and "Encoded Digital Audio." My problem seems to be that the DVD Player is forcing the audio output to be a digitally encoded signal.

How should I proceed at this point? Thanks.

Spheric Harlot · Dec 20, 2009, 01:48 AM

No. Your problem is that DVD audio is encoded in 48 kHz.

Your audio isn't syncing up.

Try setting it to 48 kHz manually in Audio midi setup, or forcing it into 44 kHz.

Ted L. Nancy · Dec 20, 2009, 09:38 AM

Perhaps I wasn't clear about my hardware setup. My Edirols are the MA-15D model stereo speakers. Unlike a larger multi-channel receiver system, they do not have a digital sound processor for translating encoded digital audio.

QUOTE=Spheric Harlot;3917517]or forcing it into 44 kHz.[/QUOTE]

Like I said, when DVD Player is playing, it changes the audio to 48. I attempted to change the frequency from 48 to 44 while DVD Player is playing, but I was unable to do so. I also tried to change the output format from encoded digital to 2-channel, but was unable to do that as well.

Originally Posted by Spheric Harlot

Try setting it to 48 kHz manually in Audio midi setup

Well I set it to 48 prior to playing the DVD in "anticipation" of the change. However, this did not prevent the DVD Player from changing the output format from 2-channel to encoded digital.

If I set my digital out as my system output and change its output format to encoded digital, the speakers will not play and the OS automatically switches the audio output to my Audiohub USB speakers as if it "knows" the Edirols cannot process and encoded digital signal.

Spheric Harlot · Dec 20, 2009, 11:22 AM

It automatically switches to the AudioHub because that is your designated system audio out.

Ted L. Nancy · Dec 20, 2009, 02:07 PM

Originally Posted by Spheric Harlot

It automatically switches to the AudioHub because that is your designated system audio out.

How's that? Not by my doing...

Originally Posted by Ted L. Nancy

If I set my digital out as my system output and change its output format to encoded digital, the speakers will not play and the OS automatically switches the audio output to my Audiohub USB speakers as if it "knows" the Edirols cannot process and encoded digital signal.

Spheric Harlot · Dec 20, 2009, 03:45 PM

Sorry. I've been very ill and won't be able to help you here for awhile.

Ted L. Nancy · Dec 21, 2009, 02:01 PM

Ok, thanks. I've been doing the option-click on the menubar volume up tot his point. I was just wondering if there was a workaround like Rogue Amoeba's Detour app (which hasn't been supported since 2005).