I've found that OPi boards are no more targeted on the multimedia aplications, because there are no more I2S and SPDIF outputs on both new boards OPi Zero and OPi PC2.
What's wrong? What's the reason?

It looks so, I had the same question and it seems in the new designs there is no more Rasspberry Pi B+ compatibility as advertised.

-> http://www.orangepi.org/orangepibbsen/forum.php?mod=redirect&goto=findpost&ptid=2163&pid=16357&fromuid=1090196

Only hope that OrangePi will figure out the error and correct it in next versions.