I've currently got the DO200 and an A20H amp and did some testing with RCA as well, and couldn't hear any hiss when turned up to full volume. It takes more volume wheel to get there with single ended but the A20H has so much power on the XLR/4.4 balanced connects it won't be a problem. It has much less power on the 6.35mm single end though. I have a heavily overclocked gaming system, and if possible always use optical if there's noise problem. I have a Febsmart USB 2 port card away from the video card as well for a silent noise floor. Just pause a song and turn the volume way up, if you don't get a hiss then, you're good.