I renamed all my sounds in a folder (not in construct). I had an ogg anf m4a version of each, same exact names, ready to go. I imported them all at once..
THEN, I edited my events that triggered sounds to reference the NEW named versions of my sounds that I had just imported (in both m4a and ogg at the same time), and now it works.
I hope this helps future non windows 7 users, because this was annoying.