(In reply to Christian König from comment #2)
> Created attachment 117336 [details] [review] [review]
> Possible fix
> 
> This should fix the issue.

Sort of - kodi seems OK with it but mpv is strange.

With mpv if I test something small/low bitrate there's a fair chance it fails
with -

[vo/opengl] after rendering: OpenGL error INVALID_OPERATION

It seems that I can make it work reliably by setting my cpus to perf with
cpufreq.

I wonder if there is some timing/threading issue here - on my phenom II x4
cpufreq is quite extreme in that low is 800MHz next is 2.2 GHz.

I will soon be filing another UVD issue I found - but after messing around with
it quite extensively I now need to put cpufreq into the testing and do it
again!