This great headphone "virtual earplugs" -removal tool, buried deep in ADI´s menus, is maybe the most undervalued feature of this RME´s little swiss army knife of audio. It is the essential setting in headphone listening, and can well determine whether critical user can continue as headphone listener or not.
To make it to affect enough, one must really just suppress their encoder 2 -hand shaking and courage themself to screw it all the way up to maximum setting 5. Milder settings doesn´t get that channel separation of <700 Hz small enough, "virtual earplugs" of headphone reproduction just won´t yet get off with those.
Of course warning of disappointment is in place with this too: crap-recordings still sound like crap, even with crossfeed 5.
Although its unquestionable properties as the naturaliser of the headphone reproduction, even proper crossfeed can´t polish real compressor-OD-loudness-war -pile of shit -recordings to parade condition. It makes them to just sound spatially more correct compressor-OD-loudness-war -pile of shit.
This should be kept in mind before skipping to next track. And at least suppress oneself to NOT go re-cycling ADI´s crossfeed setting.