Perhaps your observations are just a placebo effect?

Could you try actually timing the differences you think you've experienced between 1MB and 2MB?

Sooloos, Roon, G series (with LPS upgrade), 800 series (with LPS upgrade), HD621, AC200, Prime and PS, DSPs old and new.

Purdeys, Moke, Leica, 'Blad. Only the best.