I've been using Ubuntu 16.04 for 3 months now and it was working all peachy. But, recently it started misbehaving, doesn't shut down, doesn't sleep, and earlier, when left idle the screen used to get locked and then required the password to unlock.
But now, it just simply hangs and then I have to force shutdown/reboot every time.
Edit from comment: current kernel version is 4.13.0-37-generic
I followed this link and changed the grub file, but didn't work. I don't want to mess up anything else which I don't know about and don't want my computer to die. So, any help would be appreciated.
Thanks for your time.