Tip for "Always On" Audio (possibly works on any Mac)

Question

Those users who have a preamp &/or headphones connected to their Mac will notice a distinct "click" when the power is applied/removed from the audio chip, when sound is called. And there’s always a lag when it turns on. This has gone on far enough.
Here’s a very easy way to keep your sound chip from "sleeping":
With your audio editor of choice, (such as Audacity), generate 30 seconds of silence, and export as an AIFF file. Save to your preferred location, as <Silent Loop>, or something.
Open your preferred version of Quicktime Player, and open <Silent Loop>. Have the player just play the silence forever. No more clicks, because the chip is always "awake".
Add your loop to "Startup Items", and set Quicktime player to play files when opened, as the "set and forget" default.
This probably doesn't apply for audio via USB or FireWire.
Perhaps Apple could add a "never sleep" option to Sound Preferences/Output?
Message was edited by: MacSinceEightySix

Answer 1

MacProCT wrote:
There are two utilities that do something similar, but don't require having QT player open.
http://www.ziksw.com/old_site/soundon/index.html
http://mrfeinberg.com/KeepSoundAwake/
I suspect SoundOn is more widely compatible, since it does not use a preferencepane.
SoundOn just launched for me under osx 10.6 and stayed open. Didn't test its effectiveness (I'm not personally having a sound sleep problem).
This technote:
http://support.apple.com/kb/TA20726
includes the following (emphasis added):
In order to increase battery life, Mac OS X versions 10.1.2 through 10.1.5 turn off your computer's sound hardware when it is not used for 30 seconds. The delay in hearing sounds is the time it takes for the sound hardware to go from its low power mode to sound production.
*One way to avoid this issue is by using external USB speakers.*
Since this is a glitch that has “survived” through OS 10.6, I suppose that Apple has seen that a vast majority of users opt for USB and/or optical out, so they optimize bug-fixing “energy use” also.
Since I use QuickTime pretty regularly, and the implementation of both of those “SoundOn” apps plays silence anyway, might as well just run Apple software in the background. It shows a minimal CPU usage/RAM footprint, and I suppose it’s the audio equivalent to Preview, which I load at startup as well.
MS86
Message was edited by: MacSinceEightySix