The gods of audio have awarded my good and just behavior: An updated Oppomod I2S card replacement, a 0.5m Apollo HDMI cable as recommended by @gazjam, and an HDMI adapter that blocks pin 18 (the 5v feed) from Jay’s Audio, all arrived at the same time and just before a three day weekend! Despite previous assurances from Jaehong that the DSD channel swap issue was fixed in firmware, this particular card (labeled Ver 1.1 Rev. C -2019-02-21) has a new DSD Swap jumper (SW4):
Also note that fuse FB2 is installed, so the HDMI pin 18 blocking adapter will be needed (unless I remove the fuse).
Full report to follow…