[LAU] USB-Audio and XHCI (USB 3)

Hi everyone, I was wondering if anyone managed to run a USB 2 soundcard on a USB3 (XHCI) port? I'm running the kernel 3.2 rc7. With the M-Audio Fast Track Ultra (USB 2): The output of dmesg is this: [ 475.094595] usb 3-1: new high-speed USB device number 2 using xhci_hcd [ 475.108605] usb 3-1: config 1 interface 3 altsetting 0 bulk endpoint 0x7 has invalid maxpacket 8 [ 475.108615] usb 3-1: config 1 interface 3 altsetting 0 bulk endpoint 0x87 has invalid maxpacket 8 [ 475.108958] xhci_hcd 0000:04:00.0: WARN: short transfer on control ep [ 475.109328] xhci_hcd 0000:04:00.0: WARN: short transfer on control ep [ 475.109879] xhci_hcd 0000:04:00.0: WARN: short transfer on control ep [ 475.110564] xhci_hcd 0000:04:00.0: ERROR: unexpected command completion code 0x11. [ 475.110585] usb 3-1: can't set config #1, error -22 The snd-usb-audio module is not probed automatically, and if I modprobe it manually, no sound card is detected. The error message is described in this bug: https://bugzilla.novell.com/show_bug.cgi?id=679944 but if I understand well, kernel wise, everything is "ok" and the issue lies in Alsa The output of lsusb is: Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 001 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub Bus 002 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub Bus 001 Device 003: ID 050d:0307 Belkin Components Bus 002 Device 003: ID 0408:1af1 Quanta Computer, Inc. Bus 001 Device 004: ID 046d:c51b Logitech, Inc. V220 Cordless Optical Mouse for Notebooks Bus 003 Device 002: ID 0763:2080 Midiman M-Audio RunTime DFU The Edirol UA-25Ex (USB 1) works fine, I get a few warnings in dmesg but the sound card is detected and functional... Let me know if I should provide any more info, or outputs, anything that can help. Kind Regards, Aurélien