Started experiencing this issue a few days ago. When I boot up my laptop for the first time in the morning, I get to the splash screen to enter in my password to decrypt my hard drive, but my keyboard does not appear to work. I have tried using a USB keyboard and the laptop's keyboard, but it makes no difference.
If I hold the power button and shutdown the laptop and immediately power it on again, the appearance of the boot sequence changes. I see the grub boot screen followed by a command prompt to enter a password to decrypt the hard drive. At this point I can enter my password and complete the boot up.
Anyone have any tips on how to troubleshoot this issue?
Update (02-Oct-2015) - It looks like the keyboard is working as I have found that pressing ALT+CTRL+DELETE will reboot the laptop. Like above, on the second boot I get the grub screen and the command prompt for the password to decrypt the hard drive.
Update (06-Oct-2015) - I have managed to come up with a work around. The change removes the graphical splash screen.
- Open /etc/default/grub in a text editor
- Remove 'quiet splash' from the line GRUB_CMDLINE_LINUX_DEFAULT so that the line looks like GRUB_CMDLINE_LINUX_DEFAULT=""
- Save you changes
- run the command sudo update-grub to update the grub configuration
On your next boot you will get text console output instead of the splash screen. The boot sequence will pause waiting for the drive password. NOTE: For me, the password prompt did not show up properly until I started typing.