Alright, been through a lot of threads and a lot of solutions about this and none of them have worked so far. I'm using a RHTS-8206 headset from Rosewill, and the mic leaks in audio from my headphones to anyone in skype or ventrilo with me.
Things I've Tried: Turning off any hint or existence of stereo mix on my entire pc
Making sure my mic has 'Listen to this Device' shut off.
And making messing with all the options in the world in my Realtek HD Audio Manager.
Nothing I've found has actually managed to solve this, so I figured I'd open my own thread.