Internal speaker not working because it's treated as headphone and muted by default

[Fikrul Arif]

I am using Ubuntu Focal in HP Pavilion g4, the internal speaker not working, no sound at all. However it works if I run alsamixer and unmute the headphone. It's strange that the internal speaker is assumed as headphone.

For your information, it happens after upgrading to Focal, it was good in the previous LTS version. For additional information, I upgraded to Focal while using external monitor that has speaker by using HDMI cable. The HDMI was connected before and after upgrade process. I don't know if this is related.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: alsa-utils 1.2.2-1ubuntu1
ProcVersionSignature: Ubuntu 5.4.0-48.52-generic 5.4.60
Uname: Linux 5.4.0-48-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.9
Architecture: amd64
CasperMD5CheckResult: skip
CurrentDesktop: ubuntu:GNOME
Date: Thu Oct 1 09:23:53 2020
InstallationDate: Installed on 2018-12-23 (647 days ago)
InstallationMedia: Ubuntu 18.04.1 LTS "Bionic Beaver" - Release amd64 (20180725)
SourcePackage: alsa-utils
UpgradeStatus: Upgraded to focal on 2020-05-30 (124 days ago)