Mac Mini USB output sounds "garbled"

Boy oh boy, sounds like the Devil at work again in your system.

Try using another USB cable and use the last port ( on the right looking at the back of the Mini ) for hook up of the USB cable.

Did you try AIFF?

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.