Hello, Arkenbrien here.
First, my audio setup:
My source is my PC, with a cheap dedicated sound card (ASUS Xonar DG), running to a Denon DRA-397, powering a pair of what I believe are Kenwood JL-790. I'm slowly converting my music collection into WAV/FLAC.
My PC is kind of old, and the sound card is directly below a pretty noisy graphics card. I currently have 1/8 out to RCA into my receiver, and noise leaks through. Fortunately not a whole lot on the standard stereo output (surround sound is a different story), but I think I can do better. So I was looking at getting an external sound card, but I've decided against that because I'd like to get a CD player in the future, so getting a DAC would be the better purchase.
So I'm looking for a DAC with an optical/digital in, and has at least two inputs. I'm not particularly choosy (i.e., I have no idea what I like nor any frame of reference), but I'd like something in the mid-range. Any suggestions wouldn't go amiss.
Second, I have a persistent hiss. It doesn't matter if I have my computer on or not. I can mute/turn the volume all the way down on my receiver, and the hissing stops, so there's something going through the system.
I've done some research online and here, but I'm open to suggestions as to how to isolate the issue.
Thanks!