1945072 - Some videos do not play any audio in firefox (win 11 N)

Status: UNCONFIRMED

(Core :: Audio/Video: Playback, defect)

Description

[rhubarbgrumble]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:134.0) Gecko/20100101 Firefox/134.0

Steps to reproduce:

I haven't been able to pin down reproduction steps yet. If I can explain the issue, it might better show how that could be a very big job or might even risk working around the problem, leaving us none the wiser as to how this situation came about.

I had done a clean install of Windows 11 Pro N (24H2), along with firefox 134.0.2 and a few other programs and windows components (including the Media feature pack). I then ended up with a situation where video and audio playback does actually work just fine for many videos on this firefox (so I think that rules out there being a fairly basic windows volume mixer, muted browser tab, or windows audio playback device issue going on here). However, using a single video test web page (https://tools.woolyss.com/html5-audio-video-tester), I can see many of the videos play back both video and audio just fine in this instance of firefox, but SOME videos, which should play audio, don't play any audio at all in this particular case with firefox, while those same videos correctly play audio under a different browser (in this case, Edge). Because I have a window and linux dual boot PC, I can also see that those problematic missing audio videos play back fine in firefox on linux.

The above test page is just a convenient place to see and compare the problematic video formats; it's not like the problem is isolated to only the videos on that page; many other videos on other pages (presumably of formats similar to the problematic ones) also exhibit the same issue for this win11+firefox instance.

I have seen that the 'Media feature pack' (or lack of it) is mentioned as a suggested fix for some media problems relating to Windows 11 N. However, I have added this optional feature and the problem remains.

I have the 'Play DRM-controlled content' setting enabled in firefox.

I get the following results when comparing firefox to edge video playback for the videos on this test page (on windows 11) : https://tools.woolyss.com/html5-audio-video-tester -

(Sorry, I don't know how to align the following; it needs a fixed width font)

                       FF vid    FF audio    Edge vid    Edge audio

av1-opus-sita.webm Works Works Works Works
vp9-vorbis-spring.webm Works Works Works Works
vp8-vorbis-sintel.webm Works Works Works Works
avc-aac-nerdist-friends.mp4 Works NO SOUND Works Works
avc-aac-big-buck-bunny.m4v Works NO SOUND Works Works
avc-mp3-sita.mov Works Works Works Works

And maybe also relevant is that there's also a difference in the audio-only samples further down the table on the same page -

               FF audio   Edge audio

audio-sample.mp3 Works Works
audio-sample.weba Works Works
audio-sample.ogg Works Works
audio-sample.opus Works Works
audio-sample.flac Works Works
audio-sample.wav Works Works
audio-sample.m4a FAILS Works
ac192.mp3 Works Works
spoonradio-hd.aac FAILS Works
audio.opus Works Works

I've tried the following without success -

• Restarting Windows
• Restarting Firefox
• Restarting Firefox with addons/extensions disabled
• 'about:support' > Refresh Firefox
• 'about:support' > Clear startup cache
• (hamburger) > more tools > task manager > (click the little profile icon for the page playing the video)... This weird-sounding option was mentioned as a workaround in relation to a similar sounding problem somewhere.
• I've checked the settings suggested here: https://support.mozilla.org/en-US/kb/fix-common-audio-and-video-issues#w_check-some-firefox-settings
• A full uninstall of firefox, deleting both user profile firefox folders, reboot windows, and a clean reinstall of firefox.

As I mentioned here (https://support.mozilla.org/en-US/questions/1488011#answer-1706186), I did notice how the mozilla support 'Share Data' field was filled in with a possibly relevant set of values on my problematic win11+firefox combination (i.e. "H264 NONE" and "AAC NONE") -

"media": {
"currentAudioBackend": "wasapi",
...
"codecSupportInfo": "H264 NONE\nVP9 SW\nVP8 SW\nAV1 SW\nHEVC NONE\nAAC NONE\nMP3 SW\nOpus SW\nVorbis SW\nFLAC SW\nWave SW"
},

while my linux+firefox browser filled in notably different 'codecSupportInfo' values -
"media": {
"currentAudioBackend": "pulse-rust",
...
"codecSupportInfo": "H264 SW\nVP9 SW\nVP8 SW\nAV1 SW\nHEVC NONE\nAAC SW\nMP3 SW\nOpus SW\nVorbis SW\nFLAC SW\nWave SW"
},

so I wondered ultimately what firefox does to determine these values and if that hints at the source of the problem. As in, what is firefox doing to determine these "AAC NONE" vs "SW" values? Can I do anything with Edge (or perhaps Chrome) to see if they use different systems or do different operations that enable them to play the audio where firefox fails?

Getting better steps for others to be able to reproduce this exact issue might require some pretty laborious and repeated reinstalls of Windows 11 N, experimenting with different steps, but also might end up failing to reproduce and instead work around the issue, leaving us without any better understanding of what system/setting/dependency may have put firefox in this state. Because of this, I was hoping that, before attempting something much more time-consuming and drastic that may end up failing to reproduce this issue, and while I have it happening now, can someone suggest some more useful diagnostics or firefox internal settings to inspect that might help shed light on the source of the problem?

Actual results:

m4v (H.264 + AAC) video and mp4 (H.264 + AAC) videos play back video only, with no audio, only in this instance of firefox + Win11. These are -

https://tools.woolyss.com/html5-audio-video-tester/?u=woolyss.com/f/avc-aac-nerdist-friends.mp4

https://tools.woolyss.com/html5-audio-video-tester/?u=woolyss.com/f/avc-aac-big-buck-bunny.m4v

webm (AV1 + Opus), webm (VP9 + Vorbis), webm (VP8 + Vorbis), mov (H.264 + MP3) all play back video and audio correctly.

Also, these m4a (AAC) and aac files fail to play at all -

https://tools.woolyss.com/html5-audio-video-tester/?u=woolyss.com/f/audio-sample.m4a

https://tools.woolyss.com/html5-audio-video-tester/?u=spoonradio.ice.infomaniak.ch/spoonradio-hd.aac

Expected results:

All of the above videos should play back both video and audio in firefox, like they do in Edge (Version 132.0.2957.127) and Chrome (Version 132.0.6834.160) on the same Win 11 Pro N OS.

Also, the two audio sources that I've highlighted above as failing in firefox (+win11 N) should play back correctly, like they do in Edge and Chrome on the same Win11 OS.

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Core::Audio/Video: Playback' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 2

[rhubarbgrumble]

I gave up waiting for any suggestions on how to better diagnose how firefox appeared to have got in to this state, where other browsers seemed to work fine, so I attempted to repeat a full, clean reinstall of win11 (N), along with many windows and other application install and setup steps... and now this particular firefox audio/video playback issue is gone, which is kind of a shame since we lose the ability to learn about the problem and potentially produce a fix to prevent it from happening to others in the future... and a fix is not having o reinstall windows; that's a workaround to try to sweep a firefox problem under the carpet.

I don't think we can now get anything useful from leaving this bug open since I can't investigate the problem any more and I really don't want to spend days repeatedly tryin to reinstall windows on what is my main personal PC just to try to get firefox to choke in this way again.

Comment 3

[BugBot [:suhaib / :marco/ :calixte]]

The severity field is not set for this bug.
:jimm, could you have a look please?

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