There seems to be a regression in last kernels: in 4.4.0-57, 4.4.0-53, 4.4.0-47 the problem came back:
[ 6.674209] usb 2-1.2: device descriptor read/64, error -110 [ 20.713076] random: nonblocking pool is initialized [ 21.849908] usb 2-1.2: device descriptor read/64, error -110 [ 22.025915] usb 2-1.2: new high-speed USB device number 4 using ehci-pci [ 22.109900] usb 2-1.2: device descriptor read/64, error -71 [ 22.297898] usb 2-1.2: device descriptor read/64, error -71 [ 22.473897] usb 2-1.2: new high-speed USB device number 5 using ehci-pci [ 22.889887] usb 2-1.2: device not accepting address 5, error -71 [ 22.961884] usb 2-1.2: new high-speed USB device number 6 using ehci-pci [ 23.377873] usb 2-1.2: device not accepting address 6, error -71 [ 23.379607] usb 2-1-port2: unable to enumerate USB device The latest working kernel is 4.4.0-45. ** Changed in: linux (Ubuntu) Status: Fix Released => Confirmed -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1534948 Title: Ubuntu 15.10 fails to boot from Sandisk USB stick To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1534948/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs