I might give the other inputs a try. I doubt I'd hear much difference, but that speaks as much against my preference for TOSLINK as for your recommendation of USB (and I still haven't been able to place the speakers the way they were designed to be, either, further mudding the waters). The specs indicate that USB input is limited to 16 bit 48 kHz, with coaxial and optical apparently supporting 24 bit 192 kHz, but that's a moot point because I don't have any HD material. Of course, I could try it on my main speakers, it's powerful enough for them I think.

I bought the little brother, the DA1, for Mummy's desktop, and I think it's a rebrand, but I cannot for the life of me remember the other name, and I don't know if Argon (in-house brand of Scandinavian hi-fi chain Hi-Fi Klubben) uses a single supplier for their devices or if they just shop around and slap their name on stuff... Edit: The DA1 looks almost identical to the Big Joe III by "Firestone Audio", whoever they are. Some of the other Argon-branded products also seem to have equivalents from Firestone.

I'm using opitcal S/PDIF and never noticed anything. I always thought jitter would be caused by the source, such as a CD player, but shouldn't be an issue with ALAC/FLAC files.

Have you looked for Beresford DACs? They are tiny, hand-assembled and received raving reviews. I use one (the very basic model), however as I wouldn't describe myself as an audiophile, I'd not dare to judge its performance.

What appeals to me is the DAC + amplifier combination, the size, the volume knob (I dislike being stuck with only the computer's volume control, which isn't always handy), and the multiple digital plus an analog input. It's ideal for driving a set of passive speakers of my choice.

Can someone explain what you guys mean by "jitter"? I understand the concept of mechanical vibrations from reading a CD resulting in errors in the bitstream, but it seems like unless there is an issue with the conversion from bitstream to optical on the motherboard/sound card output end, the input to the DAC should be error-free (or at least correctable by whatever protocol is used).

Here's is a technical discussion from a D/A manufacturer of renown: http://www.benchmarkmedia.com/appnotes-d/jittercu

There is some controversy about jitter on S/PDIF. Most high end DA makers have accepted the truism among audiophiles that it is the worst (for jitter) of all the digital transfer interfaces. Here is a technical overview: http://www.audiocraftersguild.com/AandE ... itter2.htm

Thanks, Mike!