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Existing (and validated) mp3s not playing since FF36

  • 8 replies
  • 5 have this problem
  • 14 views
  • Last reply by cor-el

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Hi, since FF36 on windows, the mp3s on our websites don't play anymore. They worked fine in previous version of Firefox ... they still play on all other major browsers, and even FF36 for Mac, but not on FF36 for windows.

Firefox simply claims that the mp3 is corrupt, but Checkmate Validator says it's fine.

Funny thing is, the mp3s work again after re-encoding with Audacity (with no change in settings) but we don't really want to re-encode our whole library if we don't absolutely have to.

Here's a link to an offending mp3: http://www.calvaryem.org/wp-content/uploads/mp3/20150315AM.mp3

And here's a link to the re-encoded mp3 with Audacity (same settings): http://www.calvaryem.org/wp-content/uploads/mp3/20150315AM-stereo.mp3

Though the mp3s are slightly different, MP3 validators claim that both mp3s are valid.

Any ideas would be greatly appreciated...Thanks!

Hi, since FF36 on windows, the mp3s on our websites don't play anymore. They worked fine in previous version of Firefox ... they still play on all other major browsers, and even FF36 for Mac, but not on FF36 for windows. Firefox simply claims that the mp3 is corrupt, but Checkmate Validator says it's fine. Funny thing is, the mp3s work again after re-encoding with Audacity (with no change in settings) but we don't really want to re-encode our whole library if we don't absolutely have to. Here's a link to an offending mp3: http://www.calvaryem.org/wp-content/uploads/mp3/20150315AM.mp3 And here's a link to the re-encoded mp3 with Audacity (same settings): http://www.calvaryem.org/wp-content/uploads/mp3/20150315AM-stereo.mp3 Though the mp3s are slightly different, MP3 validators claim that both mp3s are valid. Any ideas would be greatly appreciated...Thanks!

All Replies (8)

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I've called the big guys to help you. Good luck.

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That is puzzling.

On Windows 7, the newly encoded media autostarts nearly immediately, while the old media seems to download first. Clearly "something" is different although general properties do not reveal what it is.

On Windows Vista and higher, Firefox uses Media Foundation, with a fallback to DirectShow, to decode MPEG-encoded media. I'm struggling to think of a way to test whether this issue is in Firefox or its hand-off to Media Foundation, or in Media Foundation itself after recent Windows updates.

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hmm, interesting. Maybe that would explain why its not an issue on Mac FF36?

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Also, it seems weird that it wasn't a problem in previous version of firefox...

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To re-test Firefox 35.0.1 on your current system configuration, you could use the "Portable" version. After you download the installer, it unzips into a folder and runs from there without using/disturbing your standard Firefox settings. (However, you might need to exit regular Firefox, I think they might not be able to run simultaneously.)

Portable 35.0.1

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Thanks. I just tried it out ... indeed, the mp3 plays fine with FF35. Its just a FF36 issue ...

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I think it would make sense for you to file a bug for this. The developers may recognize some difference between these MP3s that we do not, or remember a seemingly small change in Firefox 36 that we have overlooked.

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There is a bug report that looks similar:

If the file plays in Firefox35 then you can try to determine a regression range. That would increase the chances to make a developer look at it.