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Streaming video lags while Audio continues normally when switching tabs


It only happens if I go from a streaming video tab to another tab or browser screen/software etc. anything that switches the main view of my screen from the video and back will cause this problem.

it will play fine at first, but once I look at facebook or bring up itunes etc, and switch back (usually doesnt occur right away, but once the video is a minute or two in it will 100%) the video will start to lag horribly and will never get back on track. the play buttons on youtube/netflix even stay as pause buttons even though I can click play and pause back and forth functionally, and the audio will never skip a beat, but the video will stop dead, lag a few frames and stop dead again and will never correct unless I refresh the page. I can't recreate this in chrome, I've cleared my history and caches, upped the storage size on the main cache and tried updating various things like flash and firefox (19.0) but nothing is solving it!

Additional System Details

Installed Plug-ins

  • Shockwave Flash 11.6 r602
  • Octoshape Streaming Services web integration browser plug-in
  • Displays Java applet content, or a placeholder if Java is not installed.
  • The QuickTime Plugin allows you to view a wide variety of multimedia content in web pages. For more information, visit the QuickTime Web site.
  • 5.1.10411.0
  • Facebook Video Calling by Skype
  • DivX VOD Helper Plug-in
  • The Google Earth Plugin allows you to view 3D imagery and terrain in your web browser.
  • Office Live Update v1.0
  • The Flip4Mac WMV Plugin allows you to view Windows Media content using QuickTime.
  • iPhoto6


  • Firefox 19.0
  • User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:19.0) Gecko/20100101 Firefox/19.0
  • Support URL: http://support.mozilla.org/1/firefox/19.0/Darwin/en-US/


  • Adblock Plus 2.1.2 ({d10d0bf8-f5b5-c8b4-a8b2-2b9879e08c5d})
  • Add Google Search To New Tab Page 1.0.2 (newtabgoogle@graememcc.co.uk)
  • Default Theme Engine - Personas Interactive (btpersonas@brandthunder.com)
  • Media Hint 0.1.8 (mediahint@jetpack)
  • Personas 1.6.2 (personas@christopher.beard)
  • Troubleshooter 1.0a (troubleshooter@mozilla.org)
  • Adobe Acrobat - Create PDF 1.1 (web2pdfextension@web2pdf.adobedotcom) (Inactive)
  • Adobe Contribute Toolbar 6.0 ({01A8CA0A-4C96-465b-A49B-65C46FAD54F9}) (Inactive)
  • codec-M ({EEF73632-A085-4fd3-A778-ECD82C8CB297}) (Inactive)
  • DivX Plus Web Player HTML5 <video> ({23fcfd51-4958-4f00-80a3-ae97e717ed8b}) (Inactive)
  • Greasemonkey 1.1 ({e4a8a97b-f2ed-450b-b12d-ee082ba24781}) (Inactive)


  • incrementalGCEnabled: True


  • adapterDescription:
  • adapterDeviceID: 0x a29
  • adapterDrivers:
  • adapterRAM:
  • adapterVendorID: 0x10de
  • driverDate:
  • driverVersion:
  • info: {u'AzureContentBackend': u'none', u'AzureCanvasBackend': u'quartz', u'AzureFallbackCanvasBackend': u'none'}
  • numAcceleratedWindows: 1
  • numTotalWindows: 1
  • webglRenderer: NVIDIA Corporation -- NVIDIA GeForce GT 330M OpenGL Engine
  • windowLayerManagerType: OpenGL

Modified Preferences

  • accessibility.typeaheadfind.flashBar: 0
  • browser.cache.disk.capacity: 1048576
  • browser.cache.disk.smart_size.enabled: False
  • browser.cache.disk.smart_size.first_run: False
  • browser.cache.disk.smart_size.use_old_max: False
  • browser.cache.disk.smart_size_cached_value: 358400
  • browser.history_expire_days.mirror: 180
  • browser.history_expire_days_min: 30
  • browser.places.smartBookmarksVersion: 4
  • browser.privatebrowsing.dont_prompt_on_enter: True
  • browser.search.suggest.enabled: False
  • browser.search.useDBForOrder: True
  • browser.startup.homepage: http://www.google.ca/
  • browser.startup.homepage_override.buildID: 20130215130331
  • browser.startup.homepage_override.mstone: 19.0
  • browser.zoom.full: False
  • dom.mozApps.used: True
  • extensions.lastAppVersion: 19.0
  • gfx.blacklist.webgl.msaa: 4
  • network.cookie.cookieBehavior: 1
  • network.cookie.prefsMigrated: True
  • places.database.lastMaintenance: 1361599784
  • places.history.expiration.transient_current_max_pages: 104019
  • places.history.expiration.transient_optimal_database_size: 166429982
  • places.last_vacuum: 1317569001
  • plugin.disable_full_page_plugin_for_types: application/pdf
  • privacy.cpd.offlineApps: True
  • privacy.cpd.sessions: False
  • privacy.cpd.siteSettings: True
  • privacy.sanitize.migrateFx3Prefs: True
  • privacy.sanitize.timeSpan: 0
  • security.warn_viewing_mixed: False


  • User JS: No
  • Accessibility: No
  • Top 10 Contributor
  • Moderator
10753 solutions 96760 answers

You can check for problems caused by recent Flash updates and try these:

  • disable hardware acceleration in the Flash plugin
  • disable protected mode in Flash 11.3 and later (?)

Question owner

I forgot to mention that I have a macbook pro 2010 model

Question owner

the above did not solve the issue. I don't want to have to switch to chrome so can anyone help me out?

Question owner

any help would be appreciated.. retested and it only happens when switching tabs/ firefox browser screens, not other applications, so its 100% firefox. can you please fix your bugs or atleast someone reply?