lockup when trying to record with ffmpeg output

[sbrauer]

Recently discovered Radiance. I'm running the last release (0.6.1) on Mac OS X.
I'm trying to use the FFmpeg output node, but when I click the record checkbox the app hangs.
All the playing video and effects freeze, and I have to kill the process.
As far as I can tell, the ffmpeg command is never launched.
Not sure if there's a bug or if there's a usage problem on my part.
I have ffmpeg command version 5.0.1 installed via homebrew.
Happy to provide any more info to help troubleshoot.

btw: The app is really impressive and fun. Thank you for creating it and sharing it!