Hi Moore: I had try it on Win8 use intel USB 3.0 host. There is no noise happen. What OS you used? Does it also happen when you use Microsoft UAA? ________________________________ 寄件者： Moore Zhang <chinahearing@xxxxxxxxx> 收件者： wdmaudiodev@xxxxxxxxxxxxx 寄件日期： 2012/9/30 (週日) 10:10 PM 主旨： [wdmaudiodev] Re: There is noise in my audio driver with USB 3.0 controller Hi Tim: Thanks for your info and suggestion, I will try to install a win8 OS and test the USB 3 port later. 发件人:wdmaudiodev-bounce@xxxxxxxxxxxxx [mailto:wdmaudiodev-bounce@xxxxxxxxxxxxx] 代表 Tim Roberts 发送时间:2012年9月29日0:34 收件人:wdmaudiodev@xxxxxxxxxxxxx 主题:[wdmaudiodev] Re: There is noise in my audio driver with USB 3.0 controller Moore Zhang wrote: >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? Prior to Windows 8, the world of USB 3.0 is a jungle, because Microsoft does not support it. When you use a USB 3 host controller in Windows 7, you are using a driver stack provided by the host controller manufacturer. No one knows what rules they followed, or what quality control they used. There SHOULD NOT be any difference for a USB 2 device plugged in to a USB 3 port, but I know some of my web cameras do not operate in some USB 3 ports, and I have no explanation for it. I suggest you try your device in a Windows 8 system with USB 3 and see if it behaves correctly. -- Tim Roberts, timr@xxxxxxxxx Providenza & Boekelheide, Inc.