Best quality connection from Network Streamer (BluSound Node II) to Preamp (MC C2700)

I have a C2700 with the DAC2 module. Started off streaming with a Mac Mini (Roon core) and recently upgraded to a Lumin U2 Mini. Really big difference in sound quality. I tried Coaxial and USB cables between the Lumin and the C2700. The USB cable sounded much better to me. I also don’t know how much of the Lumin streamer improvement might be because of the network connection. 

That DAC2 module is decent. I have a Schiit Modi+ dac that I use for my Mac Mini. I was curious if it would sound better and the DAC2 module sounds better. 
 

I do plan on upgrading my DAC down the road. The DAC2 is convenient, but now that I have the Lumin, I really need a Dac to take advantage of the better streamer. 

I’ll agree as well regarding a stand alone DAC. For now I’d say the digital coax should be your best result. I had the Bluesound and that was my choice of connection.  
I have a Gustard DAC now.  I see a lot of posts about the Denafrips Pontus 12th. Has anyone compared to to the Gustard 26 pro.  I may be looking for a new DAC. 

You have to love when you ask a simple question here how quickly it turns into an out of control freight train. You ask what is the better option for audio out and by a short end of replies you are being told to spend 5k on a new streamer. Try all your options and go by what your ears tell you. Don’t just listen for five minutes. Try to listen to each for one to two hours and see if you experience any listening fatigue. To me that is very important. What good is a very resolving detailed sound that you can only listen to for short time and feels like razor blades in your ears. Enjoy the music!