Sound quality issues streaming from Tidal vs CD

I am hoping someone familiar with streaming from Tidal might be able to help.

I have recently installed the Pro-Ject Streambox S2 Ultra, which is a small Raspberry Pi based network bridge. I connect this to my router via ethernet cable and to my Vitus DAC (which is part of the CD player) via USB. My CD player obviously outputs through the same DAC.

The sound quality from CD is so much better than the sound quality from Tidal (I am a Tidal Hifi subscriber).

So my questions are:

1. Is this just a feature of streaming via the internet, it simply is not as good as a good quality CD transport?
2. Or is it an issue with the Pro-Ject - would something like the Autralic Aries G2 (also a network bridge with no DAC) which costs 6 times the price of the Pro-Ject, improve the Tidal stream?
3. Or is it the fact that the USB cable I am using is an entry-level £10 cable?
4. Or is it Tidal? - would Qobuz sound better?

Any advice or knowledge would be welcome.
A server run's Roon core and serves music to a player (or players). A player attaches to a USB DAC and streams music to the DAC from the server. Does that answer your question?

Qobuz has the best SQ, followed by Tidal HiFi MQA. You will need good bandwidth ISP plus good DAC to enjoy the music. they will sound better than Redbook CD in most case though sometimes I can't tall them apart. if you stream from PC, USB port can be noisy depend what PC your are using. If you have an Oppo 105 player. It has a build in app that allows you to stream Tidal internally (skipping the USB post and cable). 
1. no
2. yes and a G1 is also a good option.
3. a better USB would help and also consider AES/EBU.
4. no

The issue you have is electronic noise getting into audio signal via the streamer. 

Good luck! 
I found in my setup that tidal sounds washed out compared to ripped CDs. And that digital music sounded better stored on a solid state drive as opposed to my USB3 Drobo disk array. My setup includes an ultrarendu / LPS1.2 power supply with Auoquest USB and network cables with a direct connect to network switch in my equipment rack. On the advice of Alex Crespi at uptone audio I spent $20 on a used enterprise Cisco 2960 SI 10/100 switch (replacing a new netgear gigabit switch with an audio grade external power supply). The change in sound quality for all of my stored and streamed (Tidal) music was dramatic. Music from Tidal now sounds like CD quality recordings, but still not the quality of locally stored music. I am a retired embedded systems engineer with a fair amount of knowledge about network hardware and the only reasons I can figure for this upgrade in sound quality is generally better build quality reducing noise transfer between switch ports and a better power supply.
hope this is not too long winded and is helpful