Im using Ubuntu. My Mozilla is version 31.0. Suddenly after a reboot the mousewheel scroll is terribly slow. I noticed the following using dmesg, but not sure if it was there originally: [ 2.520227] systemd-udevd[98]: starting version 204 [ 2.645111] usb 3-1: new low-speed USB device number 2 using uhci_hcd [ 2.693832] e100: Intel(R) PRO/100 Network Driver, 3.5.24-k2-NAPI [ 2.693838] e100: Copyright(c) 1999-2006 Intel Corporation [ 2.746147] e100 0000:06:08.0 eth0: addr 0xb0107000, irq 20, MAC addr 00:01:4a:c2:c9:d4 [ 2.800087] firewire_ohci 0000:06:03.2: added OHCI v1.10 device as card 0, 4 IR + 8 IT contexts, quirks 0x2 [ 2.844185] usb 3-1: New USB device found, idVendor=045e, idProduct=00cb [ 2.844189] usb 3-1: New USB device strings: Mfr=1, Product=2, SerialNumber=0 [ 2.844193] usb 3-1: Product: Microsoft Basic Optical Mouse v2.0 [ 2.844196] usb 3-1: Manufacturer: Microsoft [ 2.872507] hidraw: raw HID events driver (C) Jiri Kosina [ 2.899369] usbcore: registered new interface driver usbhid [ 2.899373] usbhid: USB HID core driver [ 2.910516] input: Microsoft Microsoft Basic Optical Mouse v2.0 as /devices/pci0000:00/0000:00:1d.1/usb3/3-1/3-1:1.0/input/input13 [ 2.911467] hid-generic 0003:045E:00CB.0001: input,hidraw0: USB HID v1.11 Mouse [Microsoft Microsoft Basic Optical Mouse v2.0 ] on usb-0000:00:1d.1-1/input0 [ 3.300117] firewire_core 0000:06:03.2: created device fw0: GUID 0800460301f0dfb6, S400