AV1 decoding with dav1d produces no video when Frames Threads setting is set to 0 (auto)
I just built a new system and found that, unlike my old system, VLC was not properly decoding AV1 video. Upon trying to play any AV1 video, the following messages would appear:
direct3d11 error: SetThumbNailClip failed: 0x800706f4
main error: video output creation failed
main error: failed to create video output
dav1d error: Decoder feed error -1!
main error: buffer deadlock prevented
This happens on a fresh install of Windows 10.
As it turns out, going into Advanced Preferences > Input / Codecs > Video Codecs > dav1d > Frames Threads and changing that option from the default of 0 (auto) fixes the issue.
I then dug a little further and found that any value for that option over 53 causes the exact same issue; that is, 1-53 correctly playback AV1 videos, but auto and 54-64 do not.
OS: Windows 10 Pro 10.0.19041 CPU: AMD Ryzen Threadripper 3970x GPU: nVidia GeForce GTX 1070