Astral Abyss
1000+ Head-Fier
Doesn't sound appealing, particularly in light of the alleged 100 hours of factory burn-in and test.
It also doesn't sound broken (my experience with which in solid state devices results in things either just not working or being horribly and obviously distorted). But it is congested, pitchy/peaky, tonally off, harsh and mushy (a neat trick to pull off simultaneously), fatiguing and veiled.
This thing is no competition for Audio-GD's PCM1704-based stuff. No competition at all. Nor is it competition for any half-way competent CoTS/reference-sheet DAC. I'm not even, particularly, a PCM1704 fan ... but while those may not be my particular cup of tea, I've never heard one that didn't totally out class this.
Anyway, I very much doubt it is defective unless it's at the design level (maybe it's hitting the extremes of parts tolerances/sample variations, but that's still a design problem). Either way, it's a) not my problem and b) to reassess this to a useful degree I'd need multiple units from random customers.
Don't need to take my word for it ... but I highly recommend listening to one before parting with your money. The cash you save will be your own.
Not arguing with what you're hearing, but I don't feel that way about the S19 vs my DAC-19. I went into it thinking the S19 was going to be "decent" and it ended up easily outclassing my DAC-19. It's too bad your experience hasn't been that good, especially considering what a pita it is to get any kind of warranty service on these units.