On Fri, May 04, 2012 at 06:02:42PM -0400, Sergio Correia wrote: > Hello folks, Hi Sergio! I'm the xHCI (USB 3.0 host controller) driver maintainer. It helps if you Cc me directly on USB 3.0 issues; otherwise it ends up in a mail folder I check less often. > when I use the microphone of my Logitech headset plugged into a USB > 3.0 port I get a robotic-like voice; if I plug it into a USB 2.0 port, > it works normally. Can you send the output of `sudo lspci -vvv -n`? I'd like to know which USB 3.0 host controller you have. > I am testing on 3.4.0-rc5 with > 0a6ba092d1c8c75ae0c0617ef7f4e6f5043af311 as the last commit [Merge tag > 'mfd-for-linus-3.4-rc6' of > git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6]. > I observe the same behavior with a 3.3.4 kernel. Has the USB 2.0 headset ever not had a robotic voice under your USB 3.0 host? > The device is this one: > Bus 002 Device 004: ID 046d:0a0c Logitech, Inc. Clear Chat Comfort USB Headset Please run `sudo lsusb -vvv -d 046d:0a0c` with your device plugged into the USB 3.0 port. I'm wondering if the bInterval reported in the endpoint descriptors is incorrect, and you're getting a different sampling rate under xHCI than EHCI. > Here are two (noisy) small audio samples to illustrate the difference > between the recording if I use the USB 2.0 and 3.0 ports (no, I don't > use this mic to record music, but I thought it would illustrate the > problem heh) > USB 2.0-> http://www.uece.net/misc/usb-headset-problem/test-usb2.0.mp3 > USB 3.0-> http://www.uece.net/misc/usb-headset-problem/test-usb3.0.mp3 Yes, that does sound strange. :) > I am pasting my full dmesg and config below (did I miss any important > stuff there?). Can you turn on CONFIG_USB_XHCI_HCD_DEBUGGING and CONFIG_USB_DEBUG, and recapture dmesg when you plug in the device and start playing audio? It may be a large log file, so you might need to put it somewhere or zip it up. > Let me know if is there any othe r useful info I could provide. It might help to compare the USBmon output from both EHCI and xHCI, when the device is playing. Then we could see which frames the audio was being transferred in. There is documentation on USBmon in the kernel source tree: http://www.kernel.org/doc/Documentation/usb/usbmon.txt Sarah Sharp -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
