The Wyred Remedy is a great little device that can improve the sound of some transport DAC combos. I would think your combo is good enough to sound better without it though. As others have said, AES/EBU is going to be your best bet rather than RCA S/PDIF.  

Snake River Audio Boomslang SPDIF but not a coaxial design.  Snake River Audio just dropped a three conductor Takshaka SPDIF also not a coaxial design.  It's a hybrid comprised of one part silver, one red copper and one gold

N

I use a full set of Audio Sensibility cables and highly recommend them. 

If you go the AES route, I have one for sale here on AudioGon. Price is negotiable. 
https://www.audiogon.com/listings/lisbeca8-audio-sensibility-signature-se-aes-ebu-xlr-digital-interconnect-0-7-meters-interconnects

I compared the Audience Studio ONE AES/EBU Digital cable and the AudioQuest - Carbon - AES/EBU Digital Cable to the Audio Sensibility cables in my system. The Audio Sensibility was warm AND more detailed than both. 
 

To emphasize earlier comments, different devices and user preferences may lead you to chose different connection types. For my setup, I preferred a USB connection over an AES connection. Experimentation in your system is the only way to find out which you’ll prefer. 

Oyaide DR-510 / DB-510 Digital Cable

+1 for @likecap -- the DR-510 is easily the best digital coax cable I've tried (of 4 or 5). The price has gone up since I got mine, but I'd buy it again in a second. The sound is lush but resolving:

https://www.thecableco.com/dr-510-db-510-digital-cable.html?srsltid=AfmBOorHhth8DgHaCxEAfuBm0FiDAvH0b3qZ3LT2d8jsCwvRkU4nfyg4