This is a defective/junk item. There is a problem with the left (1st) microphone input, and the volume control doesn't work. When looking at the software, it seems like a very faint sound is coming through, but the volume doesn't increase when turning the knob. The right (2nd) microphone input and audio output work normally. It should be usable for those who only need to use one microphone. Someone with more knowledge might be able to fix it, but I'm not sure, so I'm selling it as junk.