Mesch
Dump the PC please. I know that PCs can be set up to provide great streaming quality, but it involves quite a bit of knowledge, software, and hardware.
(1) Buy a inexpensive streamer. A BlueSound Node 130 (not the Node 2 or 2i as they do not have a functional USB output). They have a USB port, but it is not functional for output. The the Node 130 has a great user interface, and can be found used for under $300
Another option would be the Wiim Ultra (not the Wiim Pro or Pro Plus....they do not have USB output). They are $329 new, and by all reports are excellent for the money. I have never used one, so can't comment on the user interface
(2) Buy a Denafrips Iris 12th DDC, they can be bought new for $550 from Denafrips, eBay for about $510, and $400 if you are comfortable using AliExpress. It will support your current connections, but also add AES/EBU and I2S for future proof.
(3) Use a reasonably good USB cable like the Supra Excalibur USB for $110 for 1 meter, or the DHLabs Max Bandwidth USB for $90
Total cost under $1,000, and you will end up with a very very good streaming set up with a good user interface.
(4) Alternatively you could also start with a very good entry level streamer like the Innuous Zen Mini $2,400, Auralic G1.1 $3,200, or Lumin U2 Mini $2,400. You could then bypass the use of the Iris DDC, and connect those directly to your DAC.....I'd lean to the Innuous or Lumin. Unfortunately Aurender products would be quite a bit more money.