microphone not working

[Saddy]

I tried unmuting the mic with pavucontrol, the sound dialog of unity-control-center and gstreamer-properties (see attachment).
If I click record in gnome-sound-recorder, nothing happens and the following message is thrown:

(gnome-sound-recorder:4655): GStreamer-WARNING **: Element 'gconfaudiosource' already has parent

Then I tried to record sound with audacity with all available input devices: still no sound.
I also tried removing pulseaudio and restarting but to no avail. Not sure if it's due to pulseaudio though.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: pulseaudio 1:4.0-0ubuntu11
ProcVersionSignature: Ubuntu 3.13.0-24.46-generic 3.13.9
Uname: Linux 3.13.0-24-generic x86_64
ApportVersion: 2.14.1-0ubuntu3
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: saddy 2560 F.... pulseaudio
CurrentDesktop: Unity
Date: Thu Apr 24 19:11:17 2014
InstallationDate: Installed on 2014-01-26 (88 days ago)
InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Release amd64 (20131016.1)
SourcePackage: pulseaudio
UpgradeStatus: Upgraded to trusty on 2014-01-26 (87 days ago)
dmi.bios.date: 09/02/2013
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A13
dmi.board.name: 0H3MT5
dmi.board.vendor: Dell Inc.
dmi.board.version: A00
dmi.chassis.type: 9
dmi.chassis.vendor: Dell Inc.
dmi.modalias: dmi:bvnDellInc.:bvrA13:bd09/02/2013:svnDellInc.:pnLatitudeE6430:pvr01:rvnDellInc.:rn0H3MT5:rvrA00:cvnDellInc.:ct9:cvr:
dmi.product.name: Latitude E6430
dmi.product.version: 01
dmi.sys.vendor: Dell Inc.

[Saddy (sadmail)]

Checked https://help.ubuntu.com/community/SoundTroubleshooting#Line_Input.2BAC8-Microphone_Troubleshooting
and found that I have no CAPTURE-Input device in alsamixer after pressing F4. Only "Digital" shows up.

[Daniel van Vugt (vanvugt)]

Ubuntu 14.04 reached end of standard support in April 2019:

  https://wiki.ubuntu.com/Releases

If you would like to continue with free support then please update to a
newer Ubuntu version and tell us if the problem still occurs.

If you would like to continue with Ubuntu 14.04 then there is a paid
support option detailed at https://www.ubuntu.com/esm