Using the link to the mp4 in this bug's description, video and audio are working here in Firefox 37.0.1 on Ubuntu 14.04 with gstreamer1.0-libav, gstreamer1.0-plugins-bad and gstreamer1.0-plugins-ugly installed.
For Ubuntu 12.04, which uses gstreamer 0.10, H.264 video support was introduced in Firefox 26, provided that the appropriate gstreamer plug- ins are installed - seehttp://website- archive.mozilla.org/www.mozilla.org/firefox_releasenotes/en- US/firefox/26.0/releasenotes/ Ubuntu 14.04 uses gstreamer 1.0 by default. Firefox introduced support for H.264 video with gstreamer 1.0 in Firefox 30, which was released on June 10, 2014 - see https://www.mozilla.org/en- US/firefox/30.0/releasenotes/ ** Changed in: firefox (Ubuntu) Status: Confirmed => Fix Released -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to firefox in Ubuntu. https://bugs.launchpad.net/bugs/998569 Title: Embedded MP4 only plays audio in browser window Status in firefox package in Ubuntu: Fix Released Bug description: On this page: http://blogs.msdn.com/b/b8/archive/2012/05/09/redesigning-chkdsk-and-the-new-ntfs-health-model.aspx is this link: http://media.ch9.ms/ch9/4af7/90f9956a-4b4b-404a-9f01-a8f4bcb34af7/CheckDiskImprovementsforWin8_high.mp4 Clicking on it blanks the window except for the normal set of media controls except that they are *at the top* of the window except at the bottom as usual. Clicking on the Caret in the upper right of the screen and selecting Full Screen shows the video and the audio properly. In Full Screen mode, of course... On my wife's Maverick computer with FF 11, the video plays but not the audio. ProblemType: Bug DistroRelease: Ubuntu 12.04 Package: firefox 12.0+build1-0ubuntu0.12.04.1 ProcVersionSignature: Ubuntu 3.2.0-24.37-generic 3.2.14 Uname: Linux 3.2.0-24-generic x86_64 NonfreeKernelModules: nvidia AddonCompatCheckDisabled: False AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.24. ApportVersion: 2.0.1-0ubuntu7 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC1: ron 17788 F.... pulseaudio /dev/snd/controlC2: ron 17788 F.... pulseaudio /dev/snd/controlC0: ron 17788 F.... pulseaudio BuildID: 20120423122928 CRDA: Error: command ['iw', 'reg', 'get'] failed with exit code 1: nl80211 not found. Card0.Amixer.info: Card hw:0 'SB'/'HDA ATI SB at 0xfe024000 irq 16' Mixer name : 'Realtek ALC889A' Components : 'HDA:10ec0885,1458a002,00100101' Controls : 48 Simple ctrls : 22 Card1.Amixer.info: Card hw:1 'NVidia'/'HDA NVidia at 0xfcffc000 irq 19' Mixer name : 'Nvidia GPU 0b HDMI/DP' Components : 'HDA:10de000b,10de0101,00100200' Controls : 24 Simple ctrls : 4 Card2.Amixer.info: Card hw:2 'Device'/'Elite Silicon USB Audio Device at usb-0000:00:12.1-1, full speed' Mixer name : 'USB Mixer' Components : 'USB18c3:6255' Controls : 4 Simple ctrls : 3 Channel: release Date: Sat May 12 17:29:41 2012 ForcedLayersAccel: False IfupdownConfig: auto lo iface lo inet loopback IncompatibleExtensions: Old Location Bar - ID={3205B348-523A-4fac-9BC4-9939CBF583B0}, Version=2.1.6, minVersion=3.0, maxVersion=11.*, Location=app-profile, Type=extension, Active=Yes InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release amd64 (20120425) IpRoute: default via 192.168.1.1 dev eth0 proto static 169.254.0.0/16 dev eth0 scope link metric 1000 192.168.1.0/24 dev eth0 proto kernel scope link src 192.168.1.10 metric 1 IwConfig: lo no wireless extensions. eth0 no wireless extensions. ProcEnviron: TERM=xterm PATH=(custom, no user) LANG=en_US.UTF-8 SHELL=/bin/bash Profiles: Profile0 (Default) - LastVersion=12.0/20120423122928 (Running) RfKill: RunningIncompatibleAddons: True SourcePackage: firefox UpgradeStatus: No upgrade log present (probably fresh install) WifiSyslog: May 12 08:55:07 haggis kernel: [598417.037031] ptrace of non-child pid 21143 was attempted by: wineserver (pid 21106) dmi.bios.date: 10/08/2009 dmi.bios.vendor: Award Software International, Inc. dmi.bios.version: F5 dmi.board.name: GA-MA780G-UD3H dmi.board.vendor: Gigabyte Technology Co., Ltd. dmi.board.version: x.x dmi.chassis.type: 3 dmi.chassis.vendor: Gigabyte Technology Co., Ltd. dmi.modalias: dmi:bvnAwardSoftwareInternational,Inc.:bvrF5:bd10/08/2009:svnGigabyteTechnologyCo.,Ltd.:pnGA-MA780G-UD3H:pvr:rvnGigabyteTechnologyCo.,Ltd.:rnGA-MA780G-UD3H:rvrx.x:cvnGigabyteTechnologyCo.,Ltd.:ct3:cvr: dmi.product.name: GA-MA780G-UD3H dmi.sys.vendor: Gigabyte Technology Co., Ltd. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/998569/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp