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Cannot play media. No decoders for requested formats: video/mp4

  • 3 பதிலளிப்புகள்
  • 1 இந்த பிரச்சனை உள்ளது
  • 17 views
  • Last reply by FredMcD

Suddenly, most videos won't play. Upon closer inspection of the console messages, I get the following: "Cannot play media. No decoders for requested formats: video/mp4; codecs="avc1.42E01E mp4a.40.2", video/mp4; codecs="avc1.42E01E mp4a.40.2", video/mp4; codecs="avc1.42E01E mp4a.40.2", application/x-mpegurl, video/mp4; codecs="avc1.42E01E mp4a.40.2", application/x-mpegurl"

Only on Firefox, I can play mp4 videos normally in other browsers and media players. Tried reinstalling Firefox, refreshing, restarting the browser and the computer... My about:config media.mp4.enabled is set as "TRUE".

Other messages from the console:

"[warn][id_playback] id playback error: Object { code: "DNS", description: "Device not supported", reportAs: "INFO", internalError: true } player.min.js:1:55026 [error][player_error] <empty string> Object { description: "Device not supported""

Also tried disabling hardware acceleration and restarting the browser.

I'm clueless!

Suddenly, most videos won't play. Upon closer inspection of the console messages, I get the following: ''' "Cannot play media. No decoders for requested formats: video/mp4; codecs="avc1.42E01E mp4a.40.2", video/mp4; codecs="avc1.42E01E mp4a.40.2", video/mp4; codecs="avc1.42E01E mp4a.40.2", application/x-mpegurl, video/mp4; codecs="avc1.42E01E mp4a.40.2", application/x-mpegurl"''' Only on Firefox, I can play mp4 videos normally in other browsers and media players. Tried reinstalling Firefox, refreshing, restarting the browser and the computer... My about:config media.mp4.enabled is set as "TRUE". Other messages from the console: "[warn][id_playback] id playback error: Object { code: "DNS", description: "Device not supported", reportAs: "INFO", internalError: true } player.min.js:1:55026 [error][player_error] <empty string> Object { description: "Device not supported"" Also tried disabling hardware acceleration and restarting the browser. I'm clueless!

All Replies (3)

Tried everything as instructed on these pages, no change...

If you have Windows 10 N or KN then you may not have the Media Feature Pack installed. https://support.mozilla.org/en-US/kb/fix-video-audio-problems-firefox-windows