This sounds kinda like the nvidia-quicktime bug.
If you have an nVidia graphics card and Quicktime 7 installed this can cause problems. Try updating to the latest video drivers, and if that fails, downgrade Quicktime to version 6.5.
Josh Osborne - Central Innovation
HP Zbook Studio G4 - Windows 10 Pro, Intel i7 7820HQ, 32Gb RAM, Quadro M1200