I tried ALL the suggestions I've found on the net and elsewhere.
Sound isn't working with VLC player, but only through one of my multiple audio outputs.
Of course, it's the one that goes to my HDMI splitter which goes to my Onkyo home theatre system.
So it's not a windows sound issue: Sound works everywhere else.
And it's not a VLC sound issue: Sound works on all the audio outputs EXCEPT "HDMI splitter / Onkyo receiver".
And it's not an HDMI splitter: All the OTHER sound goes through it just fine.
And it's not a codec issue: VLC is playing it just fine, just not to this one output.
Halp. 45 minutes on this.