Audio controls in System Preferences

Feb 25, 2007
Reaction score
Your Mac's Specs
Macbook Pro, 2.53GHz, C2D, 4G RAM, 250G HDD
I have been connecting my MacBook Pro to my home stereo via an off board DAC. Initially, I was pleasantly surprised by the quality of the sound, but as I have become more accustomed to it, I am hearing some nasties. All my music is on iTunes and is in the Apple Lossless format. The DAC I am using is a Musical Fidelity V-DAC II. It has three inout options, USB, Optical and Co-axial. I have only tried the USB and Optical, but I notice in the System Preferences / sound that when connected to either inputs on the DAC, the Mac's volume is maxed out and locked. I think this may be a cause of some distortion I am hearing in the mid-range. TheOptical input sounds slightly better than USB, to my ears, but both are producing similar distortion.
Is there a work around that will allow me to reduce the volume on the Mac?

Also, can anyone confirm that when connecting to an external decoder, that the Mac automatically by passes it's own built in DAC? I also have an iPod in a Wadia transport which I connect into the V-DAC via co-axial and this sounds glorious. However, I would like to be able to use my Mac as I can then utilize 'Front Row' and control things remotely.

Any thoughts?

Shop Amazon

Shop for your Apple, Mac, iPhone and other computer products on Amazon.
We are a participant in the Amazon Services LLC Associates Program, an affiliate program designed to provide a means for us to earn fees by linking to Amazon and affiliated sites.