The other problem I faced was reboot/shutdown not working and booting would get stuck approximately once out of three times. The fix is simple and involves disabling two kernel modules: “echo “blacklist dw_dmac” | sudo tee -a /etc/modprobe.d/blacklist.conf” and “echo “blacklist dw_dmac_core | sudo tee -a /etc/modprobe.d/blacklist.conf“. These problems should be gone. Source: https://askubuntu.com/questions/580666/ubuntu-14-10-startup-shutdown-issues-w-hp-pavilion-x360.
Hope it helps.