To preface - This has only started recently, which is why I'm so confused.
I have this card in a http://www.gigabyte.com/fileupload/product/2/3892/4495_big.jpg in PCIEX1_1 with SLI GTX570s in the x16 and x8 slots.
Using the headphone out with a pair of HD800s with the internal amp set for 300ohm produces no audible noise, aside from a small amount when the card is set to 44100khz which is apparently a known issue with the card. (Still saving for an external amp, don't judge ;_;)
However, using the speaker out to my ancient Hi-Fi produces an incredible amount of electronic noise, even if the card is not set to output to that channel.
To give an idea of the level - When windows sound is set to 50 and foobar is up full playing anything, the noise is just audible behind the music. When the speakers are idle, it's very apparent.
This sound is almost definitely coming from the GPUs, as it's possible to hear mouse movement that changes depending on the image surface you are going over.
What confuses me about all this is the fact that this didn't happen when I first set up my current setup, and didn't happen when I used to use that output as the primary without any changes in my PC at all.
I used to have a pair of ATH-M50s plugged into the speaker out, and there used to be no discernable noise from that output at all. However, it is now incredibly apparent when using them.
I've tried reseating all the cards, I've tried different cables, everything I can think of to try and lower this noise and I flat out have no idea now.
In addition, there is an incredibly weird noise that only sometimes plagues my inputs.
My monitor has a standard audio out for HDMI devices that are connected. After hooking my phones up to that and a little cmoy, there was no discernable noise aside from hiss that I expected. However, when that is plugged into either the onboard mic in or the STX line in, the same electronic noise as before is present in any recording or monitor over the headphone out.
What makes this increasingly confusing however is that noise was present when my cmoy was totally disabled with the battery disconnected, but both inputs connected. However, disconnect either one of the audio jacks and the monitoring goes silent.
I also tried a microphone as well as an iphone in, just to see if those had the noise, but they did not. This noise is exclusive to plugging my monitor's audio out into the PC. The monitors are hooked up to my PC otherwise solely through DVI.
I am totally and utterly bamboozled by this. I have no idea where this noise is coming from. Especially considering it was fairly loud even with the cmoy totally dead...
So those are my two issues, and I cannot for the life of me see a solution. I need the audio feed from my monitor for console audio, and I was hoping to have that routed through my PC so I could hear it using my phones rather than having to plug it directly into my HiFi. In addition, the HiFi is unusable when taking any audio at all from my PC with the exact same noise. It's silent otherwise or with other inputs.
Edited by Jademalo - 2/3/14 at 8:25am