Well... Finally, I resolved the problem... It was comm issue after all!!

I guess when connecting digital cable, the DSP must be turned off (not on stand-by). I encountered the same issue when I reconnected other transport(that was working the other day) to DSP, so I initially thought DSP was the problem, but with last hope I shut the power and connected the digital cable, and it worked again. So I did the same for MC200, and the problem was gone, like a magic.

So, guess the lesson here is that when I connect digital cable, everything need to be turned off.. Can someone explain why this might be the case?

Thank you.

DSP: DSP6000.2 MKII, Reviver,
Audio: MS200, Super Linear Power Supply 12V1A, SotM ISO-Cat6
Core+Store: ROON on ROCK