Is this still an issue? If it is, please follow https://libav.org/bugreports.html and report the issue upstream.
** Changed in: libav (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to libav in Ubuntu. https://bugs.launchpad.net/bugs/1264711 Title: SIGSEV: [matroska,webm] Unknown entry Status in libav package in Ubuntu: Incomplete Bug description: Attached is a gdb backtrace. ProblemType: Bug DistroRelease: Ubuntu 14.04 Package: libav-tools 6:9.10-1ubuntu7 ProcVersionSignature: Uname: Linux 3.12.4-custom x86_64 NonfreeKernelModules: fglrx ApportVersion: 2.12.7-0ubuntu3 Architecture: amd64 CurrentDesktop: Unity Date: Sat Dec 28 10:36:30 2013 InstallationDate: Installed on 2013-11-25 (32 days ago) InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Release amd64 (20131016.1) SourcePackage: libav UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/libav/+bug/1264711/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp