A full documentation about multiple screen capture tools and more details on ffmpeg installation and configuration is attached to this page. The scripts mentioned in this document are in CERN EOS under service account elearn and in afs user dimou.
A set of options that work:
ffmpeg -video_size 1600x1200 -framerate 30 -f x11grab -i :0.0 -f alsa -ac 2 -i hw:2 -c:v libx264 -qp 0 -preset ultrafast -strict -2 path-to-the-output-file.mp4NB! You may need to retry the command as much as 8 times before it sees the microphone!!!!!