USB 2.0 to Audio 1. Two-audio output & input,C-MEDIA CM108 chip. The duplex sound track stereo sound, can simulate 7.1 sound tracks 2. Simulates 5.1 channel professional performance, the digital playback circuit frequency response: 48 KS / SEC. 3.Audio output & input, producer promise its best timbre and high-quantity 4.Producer promise its best timbre and high-quantity