отваливаются usb-устройства (клава, мышь)

в консоли набрал cat /var/log/syslog
выдало:
Sep 28 00:04:55 kububuntu kernel: [ 5466.072443] hid-generic 0003:05D5:0624.0032: input,hidraw1: USB HID v1.10 Device [KB Multimedia keyboard ] on usb-0000:00:1d.0-1.6/input1
Sep 28 00:05:11 kububuntu kernel: [ 5481.762971] usb 2-1.5: USB disconnect, device number 84
Sep 28 00:05:11 kububuntu kernel: [ 5482.036417] usb 2-1.5: new low-speed USB device number 86 using ehci-pci
Sep 28 00:05:11 kububuntu kernel: [ 5482.133513] usb 2-1.5: New USB device found, idVendor=09da, idProduct=000a
Sep 28 00:05:11 kububuntu kernel: [ 5482.133516] usb 2-1.5: New USB device strings: Mfr=1, Product=2, SerialNumber=0
Sep 28 00:05:11 kububuntu kernel: [ 5482.133518] usb 2-1.5: Product: USB Mouse
Sep 28 00:05:11 kububuntu kernel: [ 5482.133519] usb 2-1.5: Manufacturer: A4Tech
Sep 28 00:05:11 kububuntu kernel: [ 5482.136301] input: A4Tech USB Mouse as /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.5/2-1.5:1.0/input/input61
Sep 28 00:05:11 kububuntu mtp-probe: checking bus 2, device 86: "/sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.5"
Sep 28 00:05:11 kububuntu mtp-probe: bus: 2, device: 86 was not an MTP device
Sep 28 00:05:11 kububuntu kernel: [ 5482.136467] a4tech 0003:09DA:000A.0033: input,hidraw2: USB HID v1.10 Mouse [A4Tech USB Mouse] on usb-0000:00:1d.0-1.5/input0
Sep 28 00:05:11 kububuntu kernel: [ 5482.136750] usb 2-1.6: USB disconnect, device number 85
Sep 28 00:05:11 kububuntu kernel: [ 5482.396335] usb 2-1.6: new low-speed USB device number 87 using ehci-pci
Sep 28 00:05:11 kububuntu kernel: [ 5482.494797] usb 2-1.6: New USB device found, idVendor=05d5, idProduct=0624
Sep 28 00:05:11 kububuntu kernel: [ 5482.494803] usb 2-1.6: New USB device strings: Mfr=1, Product=2, SerialNumber=0
Sep 28 00:05:11 kububuntu kernel: [ 5482.494806] usb 2-1.6: Product: Multimedia keyboard
Sep 28 00:05:11 kububuntu kernel: [ 5482.494808] usb 2-1.6: Manufacturer: KB
Sep 28 00:05:11 kububuntu kernel: [ 5482.498202] input: KB Multimedia keyboard as /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.6/2-1.6:1.0/input/input62
Sep 28 00:05:11 kububuntu kernel: [ 5482.498353] hid-generic 0003:05D5:0624.0034: input,hidraw0: USB HID v1.10 Keyboard [KB Multimedia keyboard ] on usb-0000:00:1d.0-1.6/input0
Sep 28 00:05:11 kububuntu kernel: [ 5482.501076] input: KB Multimedia keyboard as /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.6/2-1.6:1.1/input/input63
Sep 28 00:05:11 kububuntu kernel: [ 5482.501207] hid-generic 0003:05D5:0624.0035: input,hidraw1: USB HID v1.10 Device [KB Multimedia keyboard ] on usb-0000:00:1d.0-1.6/input1
Sep 28 00:05:11 kububuntu mtp-probe: checking bus 2, device 87: "/sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.6"
Sep 28 00:05:11 kububuntu mtp-probe: bus: 2, device: 87 was not an MTP device

WTF???

ну естессно не просто так я туда полез, клава и мышь периодически начали отваливаться. Отвалится - опять заработает и т.д