Unable to record audio-only recording on Mac OS Firefox

[matthewgeer]

The Express Recorder is unable to make audio-only recordings in Mac Firefox; recordings with a video component work fine.

1. Create a Kaltura Express Capture instance with the allowVideo = false setting, or simply disable the camera within the options UI. (Gear button -> Camera-> turn switch off)
2. Hit the record button.
3. Attempt to make an audio recording.
4. Hit the stop recording button.

After recording stop, instead of seeing a preview of the recording, with options to upload, download, or re-record, you will simply get a grey box with "Recording Audio Only" in the top left and no other UI elements.

I set a breakpoint in the stopRecording method in the Kaltura Express Capture JavaScript. When recording a video on FireFox, or video or audio in Chrome, the this.recordedBlobs array is filled with video/webm or audio/webm blobs. When finishing an audio-only recording on Firefox, this array is empty. It appears no data is recorded at all, so the preview playback step fails, as it has nothing to work with.

OS: MacOS 10.15.7
Browser: Firefox 84.0.2 (64-bit)

Recorder initialization script:

var component = Kaltura.ExpressRecorder.create('kalturaAudioRecorder4e', {
    ks: 'REDACTED',
    serviceUrl: 'https://www.kaltura.com',
    playerUrl: 'https://cdnapisec.kaltura.com',
    app: 'Annotation Media Comments',
    partnerId: REDACTED,
    uiConfId: REDACTED,
    entryName: 'TC-1_sdent_2021-01-20T11:11:08.000-05:00_tchur_2021-01-25T11:25:27.627-05:00',
    maxRecordingTime: 3600,
    allowVideo: false
});

Console messages:

video/webm;codecs=vp9,opus is not Supported
video/webm;codecs=vp8,opus is selected

[kaltura-hooks]

Hi @matthewgeer,

Thank for you reporting an issue and helping improve Kaltura!

To get the fastest response time, and help the maintainers review and test your reported issues or suggestions, please ensure that your issue includes the following (please comment with more info if you have not included all this info in your original issue):

• Is the issue you're experiencing consistent and across platforms? or does it only happens on certain conditions?
  please provide as much details as possible.
• Which Kaltura deployment you're using: Kaltura SaaS, or self-hosted?
  If self hosted, are you using the RPM or deb install?
• Packages installed.
  When using RPM, paste the output for:

	# rpm -qa \"kaltura*\"

For deb based systems:

	# dpkg -l \"kaltura-*\"

• If running a self hosted ENV - provide the MySQL server version used
• If running a self hosted ENV - is this a single all in 1 server or a cluster?
• If running a self hosted ENV, while making the problematic request, run:

	# tail -f /opt/kaltura/log/*.log /opt/kaltura/log/batch/*.log | grep -A 1 -B 1 --color \"ERR:\|PHP\|trace\|CRIT\|\[error\]\"

and paste the output.

• When relevant, provide any screenshots or screen recordings showing the issue you're experiencing.

For general troubleshooting see:
https://github.com/kaltura/platform-install-packages/blob/Jupiter-10.13.0/doc/kaltura-packages-faq.md#troubleshooting-help

If you only have a general question rather than a bug report, please close this issue and post at:
http://forum.kaltura.org

Thank you in advance,