Thanks for your post. I just want to reiterate, the use of external clock with N20, N30 or W20 requires a well thought out holistic approach and a commitment for SOTA digital streaming. Attaching a 10mhz master clock to a streamer is a half bake idea even with a high quality DAC. A external clock on streamer end alone will not yield full benefits in terms of musical rhythm, pace, timing, realism and phase coherence.
In order to realize aforementioned benefits, you need a music server and a DAC with master clock inputs. The external clock can then be used as a single source to synchronize timing between both digital devices ensuring jitter-free and time-perfect data transmission.
My previous setup included a N20, DA2, Ref10. While adding the Ref10 made a difference over already excellent internal clock in N20, the differences was not day n night or should I say worth $8K (clock, PC, BNC cable). I was looking for next level improvements and thanks to @mikelavigne and my dealer @gestalt audio, I now have what I believe a true SOTA digital streaming front end. I also encourage the use of high quality Ethernet switch / noise filtering device to further enhance your streaming experience.