sound dont come out of system even if system sound is not muted

[gourav]

sound does not come out of system even if the system sound is not muted.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: alsa-base 1.0.25+dfsg-0ubuntu4
ProcVersionSignature: Ubuntu 3.13.0-86.131-generic 3.13.11-ckt39
Uname: Linux 3.13.0-86-generic x86_64
ApportVersion: 2.14.1-0ubuntu3.21
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: lucifer 1736 F.... pulseaudio
CurrentDesktop: Unity
Date: Mon May 30 13:26:13 2016
InstallationDate: Installed on 2016-05-30 (0 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140417)
PackageArchitecture: all
SourcePackage: alsa-driver
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 08/10/2015
dmi.bios.vendor: LENOVO
dmi.bios.version: CFCN21WW(V1.03)
dmi.board.asset.tag: NO Asset Tag
dmi.board.name: Lenovo ideapad 5
dmi.board.vendor: LENOVO
dmi.board.version: No DPK
dmi.chassis.asset.tag: NO Asset Tag
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: Lenovo ideapad 500-15ISK
dmi.modalias: dmi:bvnLENOVO:bvrCFCN21WW(V1.03):bd08/10/2015:svnLENOVO:pn80NT:pvrLenovoideapad500-15ISK:rvnLENOVO:rnLenovoideapad5:rvrNoDPK:cvnLENOVO:ct10:cvrLenovoideapad500-15ISK:
dmi.product.name: 80NT
dmi.product.version: Lenovo ideapad 500-15ISK
dmi.sys.vendor: LENOVO