Now, before you ask yourself "why do you own a 7.1 soundcard when your headset is only capable of 2.1?", long story short, 7.1 headset died, got the Siberia and kept the soundcard for future use.
I have also connected my graphics card to my TV via HDMI to sometimes stream music to my speakers. So I frequently disable & enable the Creative SB X-Fi in the "Sound" option found in the control panel.
Now to my problem, this evening I was doing nothing different, swapping output to play some music while doing the dishes. Once done, I enabled the Creative SB X-Fi again, and noticed that horrible, horrible sound that made me trade in my previous headset (The Razer Tiamat 7.1 if you wish to know), it was static. I could also hear that when listening to certain songs, words like "eyes" and "tears" made the S' sound so horrible (only in the right driver) I had to switch song and realize this was an issue.
Also when I turn the audio all the way to max without any music on with the little volume control thing on the Siberia cord, I could loud and clear hear the volume increase and it was of that when you stroke your microphone with your finger. And when I run application such as World of Warcraft, the noise becomes almost as a screech that goes up and down depending on what I do in the game.
When I plug the headset into the onboard soundjacks, the noise is gone. At least that saves me a trip to the store for a new headset that's going to sound just as bad.
I know my PC is grounded because I've never had this issue until today, and I own a special power strip with two USB connectors on it that I used with my Tiamat due to static there as well. So I am ONE HUNDRED PERCENT sure it's the soundcard.
TL;DR: My soundcard gives me static noise, halp.
If more information is needed, feel free to ask. And sorry for the long post, figured I'd post as much information as possible.