This is a fresh install of Ubuntu 16-04 on a Thinkpad P50.
Sound works when booting into Windows, but not in Ubuntu.
No sound from internal speakers or headphones.
Sound controls all seem to work, volume controls and mute buttons work in settings as well as the keyboard sound controls (they show changing volume level etc on the screen, but there is never any sound).
I have unsuccessfully used these commands in an attempt to fix the problem:
sudo apt-get remove --purge alsa-base pulseaudio
sudo apt-get install alsa-base pulseaudio
sudo alsa force-reload
( As recommended on this site: https://www.unixmen.com/2012003-howto-resolve-nosound-problem-on-ubuntu/ )
ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: alsa-base (not installed)
ProcVersionSignature: Ubuntu 4.4.0-62.83-generic 4.4.40
Uname: Linux 4.4.0-62-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.5
Architecture: amd64
CurrentDesktop: Unity
Date: Sun Feb 5 09:43:25 2017
EcryptfsInUse: Yes
InstallationDate: Installed on 2017-02-06 (-1 days ago)
InstallationMedia: Ubuntu 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160719)
ProcEnviron:
LANGUAGE=en_AU:en
PATH=(custom, no user)
XDG_RUNTIME_DIR=<set>
LANG=en_AU.UTF-8
SHELL=/bin/bash
SourcePackage: alsa-driver
Symptom: audio
Symptom_AlsaPlaybackTest: ALSA playback test through plughw:PCH failed
Symptom_Card: Built-in Audio - HDA Intel PCH
Symptom_DevicesInUse:
USER PID ACCESS COMMAND
/dev/snd/controlC0: p 2075 F.... pulseaudio
Symptom_Jack: Speaker, Internal
Symptom_Type: No sound at all
Title: [20ENCTO1WW, Realtek ALC298, Speaker, Internal] No sound at all
UpgradeStatus: No upgrade log present (probably fresh install)
After rebooting the sound now works.
No idea why exactly, I had done several previous reboots without effect, but the one after the 'sudo alsa force-reload seems to have worked.