https://bugs.freedesktop.org/show_bug.cgi?id=106430
--- Comment #9 from Benjamin Xiao ben.r.xiao@gmail.com --- I am seeing the same thing with VLC when setting Hardware-accelerated decoding from Automatic to VA-API.
Fedora 28 RX Vega 64 Kernel 4.17.2 mesa 18.0.5 llvm 6