Dolphin uses ffmpeg to play / show the videos of the games?

[nano351]

For anyone who stumbles upon this thread later, the source of the issue was mentioned in a recent blog post. The problem is from a bug in glibc: https://dolphin-emu.org/blog/2016/12/01/dolphin-progress-report-november-2016/

I had updated from ubuntu 14.04 -> 16.04 and compiled the latest dolphin source, and hadn't realized it could have been from a system library.