This USB-C port with power and SPDIF can be connected to Nuprime's DAC or integrated amps that directly supply the power and SPDIF input.
It is labelled Extension Port on IDA-8, DAC-8, DAC-9X, AMG DAC etc.
Or WR-2 can be powered by the 5V power supply from Nuprime STA-100 when used as a set.