I figured I would chime in. Enough time has passed since selling my unit as to not anger my buyer. Please note that while my product quality issues were well documented on here, I don't hold grudges and my poor opinion of the sound is completely independent of the ownership experience.
I was greatly underwhelmed by the sound. This DAC absolutely proved to me beyond doubt, that great measurement doesn't mean great sound. When I had this in my listening room, I was in the process of upgrading dacs so I had several great pieces to compare against. Obviously they would all measure much worse than the DAC8. I had a dcs Elgar with Purcell, an Antelope Pure2, a Berkeley Alpha 2, a Mytek Manhattan 2, and my current hardware, the Meridian Ultra DAC.
The difference in sound between Okto and the others, regardless of price, was night and day. The Okto sounded like it had compressed dynamic range, narrow sound stage,and weird tonality.
I understand that some of the units I listed are several times the price, but even amongst the group I listed the rank order wasn't in order of cost.
My preference by rank.
1. Meridian Ultra Dac (i currently own this)
2. Berkeley Alpha 2 (i wouldn't recommend since no usb input)
3. Antelope Pure 2 (requires pro audio style cables on balanced output) BEST VALUE!!!
4. Mytek Manhattan 2 (almost indistinguishable sound from Antelope, but cost is much higher)
5. dCS Elgar Plus/ Purcell ( great in its day, harsh by today's standard)
6. Okto Dac8 Stereo ( would be further down but I only had 6 units on hand at the time)
For reference I'm not one for audio foolery. My cables are bulk wire. My amplifiers are Hypex. My speakers are my design and are all ScanSpeak drivers.
I recognize that the industry has devolved into madness with insane prices and snake oil everywhere. That said you just can't sum up great sound with measurements. If the DAC8 is perfect I will gladly take flaws. Don't fool yourself that you're getting the world's best DAC.
Just my $0.02
Note: I only listed components I was actually able to plug into my system that day. None of these were based on comparison across dealer demo systems. I auditioned many more including the Dave and the Rossini, but its impossible for me to campare apples to apples.