1650718 - QuickTime .mov file's audio does not play in Firefox

Status: NEW

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

Description

[Chris Peterson [:cpeterson]]

Steps to reproduce

1. Load and play https://ptgmedia.pearsoncmg.com/imprint_downloads/peachpit/peachpit/videosampleclips/krug/SteveKrug_UsabilityDemo.mov

Expected results

The video and audio will play, just like in Safari 13 on macOS 10.15.5.

Actual results

The video plays but no audio plays in Firefox. Firefox's "DevTools Media Panel" extension says this file has no audio, but Safari plays audio.

Loading the .mov URL in Chrome will download the .mov file instead of trying to play it.

Comment 1

[Chris Peterson [:cpeterson]]

Firefox wasn't even able to play this .mov file's video until 56.0a1 Nightly build 2017-06-20. Then the video would play, but not the audio.

Here is build 2017-06-20's changelog:

https://hg.mozilla.org/mozilla-central/pushloghtml?fromchange=95543bdc59bd038a3d5d084b85a4fec493c349ee&tochange=7a6baa6cca3292e8099e652b64d27e74df560874

Perhaps this file was previously rejected by the Stagefright MP4 parser and enabling the new Rust MP4 parser (bug 1370175) allowed Firefox to load it for the first time?

Comment 2

[Chris Peterson [:cpeterson]]

I can still reproduce this bug in Fx 128 on both macOS 14.4 and Windows 11:

• Safari play the video and audio.
• Firefox plays the video but not audio.
• Chrome doesn't recognize the .mov file and downloads the file instead of trying to play it.