In my mind, such an explanation for the streamer influence on sq seems very tenuous, but who knows...
What we do know is that whatever JPlay can possibly do to affect the sound quality while retaining 'bit-perfection' is so dependent on variables beyond its control so as to be, for all intents and purposes, random. That is why, I believe, they offer their users so many complex options. If they were entirely confident in what they were doing they would say, here you are, this is it; no options.
Certainly, in the case of USB transmission to a DAC, amongst the most significant of those variables is the susceptibility of the DAC itself to noise (or whatever) present at its input. Suffice it to say that a good device will be more or less immune to such external variables.