Comment 0 for bug 1239545

If not then this bug can be closed
Otherwise in /src/service.vala

   var env = Environment.get_variable ("DESKTOP_SESSION");
   string cmd;
  if (env == "unity")
   cmd = "gnome-control-center sound

should be "ubuntu"

ProblemType: Bug
DistroRelease: Ubuntu 13.10
Package: indicator-sound 12.10.2+13.10.20131011-0ubuntu1
ProcVersionSignature: Ubuntu 3.11.0-11.17-generic 3.11.3
Uname: Linux 3.11.0-11-generic x86_64
ApportVersion: 2.12.5-0ubuntu2
Architecture: amd64
Date: Mon Oct 14 02:33:01 2013
InstallationDate: Installed on 2013-08-07 (67 days ago)
InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Alpha amd64 (20130803)
MarkForUpload: True
SourcePackage: indicator-sound
UpgradeStatus: No upgrade log present (probably fresh install)