User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:59.0) Gecko/20100101 Firefox/59.0 Build ID: 20171220121833 Steps to reproduce: 1. Install Windows 10 Insider Preview, build 17063 2. Install Firefox (likely any supported version, tested 57 and 59 nightly) 3. Navigate to https://hpr.dogphilosophy.net/test/ Actual results: Sound plays Expected results: Sound does not play, browser console reports Media resource https://hpr.dogphilosophy.net/test/opus.opus could not be decoded, error: Error Code: NS_ERROR_DOM_MEDIA_MEDIASINK_ERR (0x806e000b) Details: OnMediaSinkAudioError

Likely a bug on Microsoft's end, but could also be Firefox doing something weird/underspecified? Also reported to Microsoft here: https://aka.ms/W0vg77

(In reply to me from comment #1) > Likely a bug on Microsoft's end That's already been confirmed by a senior software engineer at Microsoft: https://www.reddit.com/r/Windows10/comments/7kzt7s/psa_if_you_use_firefox_dont_upgrade_to_17063_it/drjr3c6/

Unfortunately, it has also been confirmed that the issue will not be fixed in the current build, and possibly not in the next build either. Official response from a Microsoft dev here: https://www.reddit.com/r/Windows10/comments/7kzt7s/psa_if_you_use_firefox_dont_upgrade_to_17063_it/drjvc8w/ More technical explaination here: https://aka.ms/Sz9xy9 (spoiler: they broke an API). > Windows has several audio volume APIs - IAudioEndpointVolume, IChannelAudioVolume, ISimpleAudioVolume, and IAudioEndpointVolume. These APIs can be used to change the volume and/or mute state of the stream, app, or audio device. > In build 17063 a change was made to these APIs to have them return S_FALSE (1) if the requested change was a no-op. > This broke apps (like Firefox) which request changes (that may be no-ops) and then explicitly check the return value against S_OK (0). Any chance we can see a workaround on the side of Firefox?

Can someone provide the status of this now? I am seeing this error when running some tests on SauceLabs. Thanks

Nevermind just saw the duplicate ticket.