The problem with blind testing is twofold - firstly the minute you add stress into listening, then your sensitivity falls. If the actual DUT is not identified (A B or C) and truly random, then sensitivity collapses even more.
The second issue is qualitative. I remember a research paper "proving" that a Stradivarius violin was as good as a modern inexpensive violin. They blind tested these violins, and half the audience preferred one, the other half preferred the other. So there you have it - they sound the same. Of course, that was nonsense - the Strad is warm sounding, the modern violin is quite bright. If they had re-framed the question to which is the warmer sound, then you would have got the right answer - the majority of the audience would easily be able to spot the warmer violin. I once heard on the radio in my car, somebody doing a blind test with a Strad against a modern violin, and it was easy to hear which was the Strad - even in my car on the motorway - the Strad sounded a lot warmer. But some people like bite and a bright sound; and the same is true with audio. The issue with DAC's sounding different is actually not that they sound very different, but that some people actually "like" or rather think they like, the sound of distortion.
I actually employ blind listening tests when the results of a test is so challenging or significant technically, and so I need to confirm my own listening tests. So listeners are asked to hear this, hear that, without knowing what they are listening too, and characterise and describe the difference. If under blind conditions it is audible, then it means one has to accept the evidence as fact, even if intellectually it may be challenging (the ear/brain can't be that sensitive)...
But I don't see your problem - try one at home, and if you don't like it send it back. If you can't hear the difference, then don't waste your own money.
And yes sometimes I do wonder why I go to all this trouble posting technical stuff...