Hi Guys: I happened to find that when I plug in my USB 1.1 audio device in the USB 3.0 controller port, there will be noisy when playing music with WMP. But if plug in USB 1.1 or 2.0 controller port, always fine. I'm prepared to analyze and debug the driver code now, but before that does any guy in this list has similar experience of this issue? Should AVStream audio driver make special process for USB 3.0? Detail info: 1. AVStream USB audio driver. 2. Audio Device: C-Media CM106 like USB 1.1 asic 3. System: Win7 32 4. Scenario: smooth with USB 1/2 controller port; in some USB 3.0 controller port, there is noisy.