Comment # 48 on bug 1039163 from Dave Plater

Can you reinstall your ffmpeg libraries from:
http://pmbs-api.links2linux.org:8080/home:/davepl/Leap_42.2/
and see if the problem comes back.
I think this is a bug in gstreamer-plugins-libav, it's not supposed to use
libavcodec hardware codecs and this use has been disabled in 1.9.x versions.