Originally Posted by Chodi
You unplug from the amp and the noise stops. Something is causing a high frequency oscillation which is probably in both channels but better isolation in the right channel (very low level). If it doesn't see the amp load it is silent. Check for dc offset at your output. Change your cables to your amp (impedance matching could be a problem). If it is coming from your power supply then disconnecting the amp should make no difference.
I unplugged RCA connection to amp just to be sure it's not amp related problem, which it clearly isn't. I don't hear a thing in right channel, even when right channel is still in. I switched to my old RCA cables (which are like 20 times cheaper than the ones I have now) and nothing changed, noise is still there. I have one spare power cable and I tried 4 different combinations and noise in left channel persisted in all occasions. I even tried switching between IsoTek Orion and direct outlet (without any filtration) without any luck. I also tried my old amp and that left channel noise is still audible, but to much smaller degree. My old amp has a lot of background noise with highly sensitive headphones and I didn't hear the high pitching noise until I was way too high with volume - on normal listening levels it wasn't there.
I will try to set X-Sabre + amp up in another room, to see (hear) if it changes...
I really hope it's something I could fix (or something I know I can do nothing about), I really hate the idea of returning it, I waited so long for this and it will take long time to get it back again. Another problem is - I didn't buy it directly from Matrix, I got it from a french site http://www.audiophonics.fr/ , I cannot be sure that same issue will audible in other setups (I could barely hear it when I changed the amp, and I am pretty sure very sensitive headphones are needed to hear it).
EDIT: I moved amp+dac into another room, no change, issue persists. But, I noticed something very strange. When there is no RCA connected to amp, there is absolutely nothing to hear, complete dark background across whole volume range (props to amp for that btw). When I connect both channel (RCA cables), issue is starting to be audible in left channel at around 8 o'clock, annoything somewhere between 9 and 10 o'clock. However, when I switch channels (only on amp - so left channel from X-Sabre goes to the right on amp and right to left), noise is not switching channels! It still persists in left channel with same intensity as if channels were correctly connected. I guess this might not be X-Sabres fault after all...
Edited by filuS - 9/21/13 at 9:29am