Hi Allen, thank you for quick reply. It is VERY much appreciated. The output of /sys/kernel/debug/usb/devices can be found here: http://pastebin.com/HyzefGyB (I believe the relevent portion is at the end, the "Focusrite Scarlett" device). According to the output of "cat /boot/config" the CONFIG_USB_XHCI_HCD is modulaized. So can I simply "modprobe -r" it like any module? I have yet to try the 4.5 kernel. I prefer to use a low-latency kernel, bc the primary purpose of this machine is recording music. So I have been downloading the newest source code available in the Ubuntu Studio repositories, configuring with the xhci drivers modulized (by default Ubuntu makes them builtin), and compiling from that. If I download the source for 4.5, is there somewhere I can find a .config file that would allow for low- latency performance? -- 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