[HP EliteBook 725 G2, Realtek ALC3228, Black Headphone Out, Right] No sound at all

Hello
When I am plugging external headphones jack in the the headphone output of HP EliteBook 725G2, in the Sound Output window, device through which sound supposed to be playing, changing from "Speakers"to "Headphones". However, no sound is coming via headphones
I tried with 3-pin headphones and 4-pin (the one that is with mic)
Do I need to load some extra drivers in order that Ubuntu recognizes and plays the sound correctly via headphones?
System info:
lsb_release -rd
Description: Ubuntu 14.04.3 LTS
Release: 14.04

apt-cache policy alsaplayer-jack
alsaplayer-jack:
  Installed: (none)
  Candidate: 0.99.80-5.1ubuntu1
  Version table:
     0.99.80-5.1ubuntu1 0
        500 http://az.archive.ubuntu.com/ubuntu/ trusty/universe amd64 Packages

Thank you,
Arthur

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: alsa-base 1.0.25+dfsg-0ubuntu4
ProcVersionSignature: Ubuntu 3.19.0-33.38~14.04.1-generic 3.19.8-ckt7
Uname: Linux 3.19.0-33-generic x86_64
NonfreeKernelModules: wl fglrx
ApportVersion: 2.14.1-0ubuntu3.18
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: krasnov 6063 F.... pulseaudio
 /dev/snd/pcmC1D0c: krasnov 6063 F...m pulseaudio
 /dev/snd/controlC1: krasnov 6063 F.... pulseaudio
CurrentDesktop: Unity
Date: Tue Nov 17 21:45:39 2015
InstallationDate: Installed on 2015-10-13 (35 days ago)
InstallationMedia: Ubuntu 14.04.3 LTS "Trusty Tahr" - Beta amd64 (20150805)
PackageArchitecture: all
SourcePackage: alsa-driver
Symptom: audio
Symptom_AlsaPlaybackTest: ALSA playback test through plughw:Generic failed
Symptom_Card: Built-in Audio - HD-Audio Generic
Symptom_DevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: krasnov 6063 F.... pulseaudio
 /dev/snd/pcmC1D0c: krasnov 6063 F...m pulseaudio
 /dev/snd/controlC1: krasnov 6063 F.... pulseaudio
Symptom_Jack: Black Headphone Out, Right
Symptom_Type: No sound at all
Title: [HP EliteBook 725 G2, Realtek ALC3228, Black Headphone Out, Right] No sound at all
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 07/22/2015
dmi.bios.vendor: Hewlett-Packard
dmi.bios.version: M84 Ver. 01.08
dmi.board.asset.tag: Base Board Asset Tag
dmi.board.name: 221D
dmi.board.vendor: Hewlett-Packard
dmi.board.version: KBC Version 63.15
dmi.chassis.asset.tag: 5CG53566VS
dmi.chassis.type: 10
dmi.chassis.vendor: Hewlett-Packard
dmi.modalias: dmi:bvnHewlett-Packard:bvrM84Ver.01.08:bd07/22/2015:svnHewlett-Packard:pnHPEliteBook725G2:pvrA3009CD10303:rvnHewlett-Packard:rn221D:rvrKBCVersion63.15:cvnHewlett-Packard:ct10:cvr:
dmi.product.name: HP EliteBook 725 G2
dmi.product.version: A3009CD10303
dmi.sys.vendor: Hewlett-Packard