Help with Rega DAC set up

The toslink sounds better... Glass optical.

I also have the Pangea adapter. The cord does make a considerable difference. I have used several including Shunyata, Oyaide and PS Audio. I would use coax myself; some friends were over last Sunday and we tried several; they all sounded different. As with power cords which you prefer will depend on your system and your taste. I am using a Clearer Audio silver cable just now; have also used a silver Oyaide 510 and Van den Hul "The First Ultimate". Many standard ICs will work but not all; try what you have on hand. The 5 filter positions also have a significant effect; I use filter 5 most of the time but again tastes will vary. Good luck; it is a very good dac. I like the NOS approach I am considering getting a more expensive dac using this method.