Mac Mini USB output sounds "garbled"

I just purchased a MacMini, (my first Mac) for audio use.
Running it via USB into the PS Audio PWD (toslink adapter on order).

I notice inconsistency in the sound. Sometimes it sounds outstanding, other times it starts to sound lean and harsh. On one of these latter occasions, I pulled out the USB cable on the mac side, and reinserted it into the same port, and better sound returned.

Any thoughts on why this occurred?

r

Also,

Why would AIFF be better than wav in this context?

I am new to all this, and assumed that downloading into wav was ultimately going to be the most flexible way to start my computer audio files, as I don't have that many CD's in my collection.

Hopefully this is complementary to the original poster's questions; not trying to hijack the thread here.

Why would AIFF be better than wav in this context?

AIFF is an uncompressed format native to Mac, whereas WAV is also uncompressed, but native to PC. If you rip to WAV on a MAC it may be more problematic managing metadata like the album artwork or file info should you move your files around. You will notice that you cannot add album artwork, via drag-and-drop, to a WAV file ripped and stored on a MAC in iTunes. WAV files do not support metadata actually - I believe it is stored in iTunes via the software. AIFF files will have no such challenges, and still give you the quality of an uncompressed file format.

To the original poster: You said the sound was garbled via the USB connection to the DAC, whereas the CD direct connection sounds fine. Which DAC are you using? It could have something to do with the USB interface with the specific DAC - the conversion of USB to S/SPDIF. With the CD which interface are you using - Optical or RCA or BNC? Seems to me the USB has to be the problem. A quick experiment if you have the proper cable; on the MacMini run a Toslink (optical cable) from the Mini to your DAC and play the same selections that are giving you problems via USB and see if those problems are still audible. If not, the USB interface is where the problem lies. I believe you'd need a mini-toslink>toslink cable to try this.

Jax2: I'm using a Cambridge Audio DacMagic. I'm running USB 2 out of the Mini into USB 1 in the DacMagic. I will try the toslink next.

Yo Devilboy it's Dave from Renee's party!! What up B!! I think your problem may be with the USB2 going into the USB1. You can go USB1 into USB2 but can have issues with the other way around. Have you configured the Mac for the converter? When using USB on the Mac for audio you may have to configure the DAC. It's located in SYSETM HD/Utilities/Audio MIDI Setup. I think using the toslink is best for now because there is no setup for that. If you are wanting better converters try on of these http://www.mercenary.com/prsodrdatwoc.html or one of these http://vintageking.com/Weiss-DAC2-D-A-Converter or maybe one of these http://vintageking.com/Lavry-DA924?sc=18&category=500 The Weiss and the Lavry Gold can hook up directly to the mac via firewire.