@DrewDad,
I need more description, less sound!
That's right along the lines of what I thought this was -- some
sound that everyone recognizes because it's used but not captioned, and then people started saying it (I think I've seen people say it out loud but I've also seen it captioned -- most recently on "Project Runway"). It was that usage -- people
saying "wah wah," captioned as the words "wah wah" -- that got me wondering what the reference was.
This (descriptions + comments) is helping though, thanks!