There’s one item I was going to ask you about since you said it makes audible differences:
Surely whatever you’re hearing must be due to the noise shaper, if you go with their recommended settings and use 4x or more oversampling, no? How could you possibly hear if the filter’s slope is god-tier or just-good, once it’s way up at 176k or wherever? Unless I’m missing something, once generous oversampling is used, all those gazillions of taps to get as vertical of a filter slope as possible is just a way to use your CPU as a space heater, right? 