@lordmelton your praise of the 005 ultimately pushed me to get it and I thank you.
Innuos Zenith MK3 with Phoenix Reclocker and Ethernet Switch, Wireworld Platinum Starlight USB cable.
My clipping issue is most likely within the SU-R1000 used as a not preamp preamp, but I'm of the opinion that it's ADC does add something that my previous test preamp (Benchmark HPA4) didn't.
My JC1+ aren't being worked too hard, but they're just getting clipping from the SU-R1000 in sure.