Jason is an exemplary rep for AK and an asset to the company. I would hire him in a heartbeat.
After contemplating about what to do about the deteriorating sq of the sp2000 and listening to some tracks that I remembered as sounding astounding before the deterioration, (because they sounded so underwhelming), I decided to erase everything by going to system reset -> factory data reset. I figured I have nothing to lose at this point. I thought it would set everything back to fresh out of the box state, but the fw did not go back to the factory setting but remained at 1.19. So, they are correct in saying that you cannot go back. Everything on the internal hard drive was erased, as expected and I had to download Tidal and Qobuz again which didn't take up too much time. So far, I am liking what I am hearing and am hopeful that fixed the deteriorating sq. Listening to the same tracks is also promising, sounding more clear, crisp, and dynamic... anything that reverberates and gives sense of the space in which recording took place is back on par. Someone here also said theirs sounded flat, which I agree with wholeheartedly, like an opened can of coke that has been sitting out all day. It is little too soon to tell and I will probably need about a week of listening to be sure, but I do not want to sell it off like I did before I did the factory reset. It might be worth trying if you are having the same problem.
I cannot explain or understand what is happening, but I think the effect is incremental and additive with many fw updates. In other words, the sq on your sp2000 might vary if you purchased it only a month or two ago having to update only one or two fw's compared to someone who's had 3-4 updates, etc. Just my guess by reading between the lines of the different reactions of the members on this thread. I had mine since the release and went through all of the updates. I think it is also possible that only someone like me are experiencing the deterioration, and equally possible that the amount of deterioration varies.
I hope this helps some of the owners here in despair.