Locks up on sleep and powerdown

[https://www.reddit.com/r/Dell/comments/63cavx/fixed_nvidia_1050_freezing_in_ubuntu_linux/]

Modify /etc/default/grub

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_rev_override=1"

No audio in headphones

The headphones are detected but there is no audio. They work fine in windows. Solution:

alsactl restore