Streamer question

This is what I use, 1 for each of my 3 DACs. I ONLY use ROON, so this lower end Rendu model works perfectly. The more expensive ones support other streaming services protocols. This one only does RATT.

I compared this with the $15k Lumin X1 streamer/DAC which I also owned before. Both are great.

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If you decide to keep roon, I recommend you to use a NUC with rock kit installed that will be your streaming server. Plus you can still your NAS if you want. NUC and dac connected to Ethernet wire separately. No connection between the two and no usb involved. I had this configuration with success for a while. 

Excellent Holo Audio streamer.  I have the Cyan 2 and love it.  I picked up an Innuos Zen Mk3 streamer with 1TB storage to rip CDs and the pairing sounds great.  Got it used from a helpful local dealer for $1800.  Innuos has a range of streamer options and prices and have excellent customer support.  

I use Cambridge Audio CXN 100. Mainly I listen to my own ripped CDs from my NAS. I also use the AirPlay and Chromecast functions to stream from my streaming services (Apple Music and Pristine Classical) but the CA will handle both Tidal and Qobuz directly. The CA also does Internet Radio and Podcasts quite well.

My Melco NAS is also a renderer and accepts Tidal and Qobuz. It lacks the other features of the CA and the OP already has a NAS.

  I don’t use Roon

The most recommended connection for the Holo May is the USB between The DAC and a streamer. I know you said you wanted to get rid of USB connection, but maybe there is another way to do what you want and keep the USB. I use the Lumin U1 to the Holo May via USB and it sounds fantastic.