Ao inicializar no Ubuntu 16.04 (mesmo sem dispositivos USB conectados), eu me deparo com o seguinte:
[ 1.931104] usb 3-7: new low-speed USB device number 4 using xhci_hcd
[ 7.043191] usb 3-7: device descriptor read/64, error -110
[ 17.259287] usb 3-7: device descriptor read/64, error -110
[ 17.475280] usb 3-7: new low-speed USB device number 5 using xhci_hcd
[ 22.587338] usb 3-7: device descriptor read/64, error -110
[ 32.803433] usb 3-7: device descriptor read/64, error -110
[ 33.019425] usb 3-7: new low-speed USB device number 6 using xhci_hcd
[ 33.020984] usb 3-7: Device not responding to setup address.
[ 33.224987] usb 3-7: Device not responding to setup address.
[ 33.427426] usb 3-7: device not accepting address 6, error -71
[ 33.539431] usb 3-7: new low-speed USB device number 7 using xhci_hcd
[ 33.540989] usb 3-7: Device not responding to setup address.
[ 33.744991] usb 3-7: Device not responding to setup address.
[ 33.947431] usb 3-7: device not accepting address 7, error -71
Eu também tentei inicializar em uma sessão ao vivo, mesmo problema (sem dispositivos USB conectados).
Não tenho ideia de por onde começar a depurar porque esse erro é exibido mesmo sem dispositivos USB conectados ao computador. Aqui está minha saída lsusb (com alguns dispositivos USB conectados):
$ lsusb
Bus 002 Device 002: ID 8087:8001 Intel Corp.
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 8087:8009 Intel Corp.
Bus 001 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 003 Device 008: ID 1af3:0001
Bus 003 Device 003: ID 5986:066d Acer, Inc
Bus 003 Device 002: ID 0582:012f Roland Corp. QUAD-CAPTURE
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
$ lsusb -t
/: Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/6p, 5000M
/: Bus 03.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/14p, 480M
|__ Port 1: Dev 2, If 0, Class=Vendor Specific Class, Driver=snd-usb-audio, 480M
|__ Port 1: Dev 2, If 1, Class=Vendor Specific Class, Driver=snd-usb-audio, 480M
|__ Port 1: Dev 2, If 2, Class=Vendor Specific Class, Driver=snd-usb-audio, 480M
|__ Port 1: Dev 2, If 3, Class=Vendor Specific Class, Driver=snd-usb-audio, 480M
|__ Port 1: Dev 2, If 4, Class=Vendor Specific Class, Driver=snd-usb-audio, 480M
|__ Port 6: Dev 3, If 0, Class=Video, Driver=uvcvideo, 480M
|__ Port 6: Dev 3, If 1, Class=Video, Driver=uvcvideo, 480M
|__ Port 9: Dev 8, If 0, Class=Human Interface Device, Driver=usbhid, 12M
/: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/2p, 480M
|__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/8p, 480M
/: Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/2p, 480M
|__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/6p, 480M
Qualquer outra coisa que eu possa fornecer para vocês?