Ok, I know I should not, but here I am trying anyway.
First, in all the lingo, acronyms, model number cryptology, we have no idea what it is you are talking about. duh?
Second, you are talking about totally subjective assessments of sound quality relevant to you and only you. But, we cannot hear what you are hearing, prefer what you prefer, etc.
So, what does "my DAC sounds flat" actually mean? What is your point? I do not think you will get anything remotely resembling an answer here. We have no clue.