@jim204 Interesting that the JCAT USB card made a major improvement for you. I have a JCAT NET Femto ethernet card on order for installation in a QNAP i5 NAS that hosts Roon core in conjunction with SOtM EN-to-USB endpoints. I'll try powering the JCAT externally with either a SOtM or Chinese Zerozone PS. If that goes well, I may try comparing a JCAT USB card in the QNAP to the SOtM pieces-- which in my system are souped up with a Hynes SR7 linear power supply and clock links to a 10mhz master clock that also synchronizes the Esoteric DAC.
So far my computer audio set-up equals or surpasses my Esoteric K-01X transport. The performance of computer audio implementations vary widely-- which is reflected in the wide variation of responses on this topic.