not a shred of reality displayed here.
the analog audio jack they seek to replace is the final analog output of a digital to analog converter or DAC.
one cannot speak of a digital speaker, and a digital amplifier does not usually refer to using the loading of the speaker driver to smooth-out the pulse-chain like some motors on a PWM line... not in any high fidelity audio anyway...
where is the DAC or audio codec to be located? 
are we not just pushing it out to the device and pretending it went away?
why the assumption for headphones or consumer audio?
what about USBs derived clock and jitter?
why on