You have a beautiful system. You should use a S/PDIF cable that equals the quality of your components. So yes, a high-end cable. Cables do make a difference, you want a bit perfect transfer from the streamer to the DAC. It doesn’t have to be high priced, a good design is most important. In addition to design and construction, proper length plays a role in the delivery of data, typically 1.5 to 2 meters.
75ohm SPDIF coax that I have used; Acoustic Zen, Oyaide, Cerious Technologies, and currently using High Fidelity Cables. There was an audible difference between each of them.
The brand I see consistently being recommended is Black Cat.