alsactl --file ./config.txt store does not save Monitor of Built-in Audio Analog Stereo level

[Eduardo]

lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 16.04.3 LTS
Release: 16.04
Codename: xenial

Steps to reproduce the bug:

1. Click on the volume icon on the pannel, and then on Sound Settings
2. Click on label Input, then on Monitor of Built-in Analog Stereo, under Choose a Device for Sound Input
3. Move the slider above (input ...) to, say, about 50%
4. Type in a console: alsactl --file ~/.config/asound.state store
5. Move the aforementioned slider to 100% or anywhere else.
6. Type in a console: alsactl --file ~/.config/asound.state restore
7. Look at the slider. It should have been restored to 50% but it hasn't been.

apt-cache policy alsa-utils:
alsa-utils:
  Installed: 1.1.0-0ubuntu5
  Candidate: 1.1.0-0ubuntu5
  Version table:
 *** 1.1.0-0ubuntu5 500
        500 http://us.archive.ubuntu.com/ubuntu xenial/main amd64 Packages
        100 /var/lib/dpkg/status

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: alsa-base 1.0.25+dfsg-0ubuntu5
ProcVersionSignature: Ubuntu 4.10.0-28.32~16.04.2-generic 4.10.17
Uname: Linux 4.10.0-28-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.15
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/pcmC0D0c: eguerras 1767 F...m pulseaudio
 /dev/snd/pcmC0D0p: eguerras 1767 F...m pulseaudio
 /dev/snd/controlC0: eguerras 1767 F.... pulseaudio
CurrentDesktop: MATE
Date: Fri Feb 2 16:44:00 2018
InstallationDate: Installed on 2018-01-28 (5 days ago)
InstallationMedia: Ubuntu-MATE 16.04.3 LTS "Xenial Xerus" - Release amd64 (20170801)
PackageArchitecture: all
SourcePackage: alsa-driver
Symptom: audio
Symptom_AlsaRecordingTest: ALSA recording test through plughw:PCH successful
Symptom_Card: Built-in Audio - HDA Intel PCH
Symptom_PulseAudioRecordingTest: PulseAudio recording test through plughw:PCH successful
Symptom_Type: None of the above
Title: [HDA-Intel - HDA Intel PCH, recording] Recording problem
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 11/06/2012
dmi.bios.vendor: Acer
dmi.bios.version: V2.08
dmi.board.asset.tag: Type2 - Board Asset Tag
dmi.board.name: Mimic
dmi.board.vendor: Acer
dmi.board.version: Type2 - Board Version
dmi.chassis.type: 10
dmi.chassis.vendor: Acer
dmi.chassis.version: V2.08
dmi.modalias: dmi:bvnAcer:bvrV2.08:bd11/06/2012:svnAcer:pnV5-171:pvrV2.08:rvnAcer:rnMimic:rvrType2-BoardVersion:cvnAcer:ct10:cvrV2.08:
dmi.product.name: V5-171
dmi.product.version: V2.08
dmi.sys.vendor: Acer