Hi,
Our previous D100pro plays DSD via DOP, but the D300REF and D300 outputs native DSD from the RJ45 interface.
You see we have different line sequences for DSD and PCM, if you listen to DSD, then you can choose the one on the right because it can also play PCM.
I attach an article with below link talking about DSD, DOP and PCM, which is written by my boss, also the chief engineer of Soundaware.
http://www.sohu.com/a/222237159_121611
You may look at it, it should explain somehow about the problem and the reason that we customized a SAW_link interface for MR1 and P1. Words are Chinese, you may use google to translate, and I will translate it once I have time.
Thanks