handling audio/wav

As installed, mozilla, firebird and firefox all know how to handle
audio/x-wav files by starting up QT.  I recently stumbled across a
site that sends WAV files as audio/wav rather than audio/x-wav, and
none of these browsers can handle it.  I've been digging through the
Preferences windows to see if I can tell it "Just handle audio/wav
like you handle audio/x-wav".  But I haven't succeeded.  They always
pop up a window asking me what to do with the files, and I can't find
anything that works.

Anyone know?  Is it documented somewhere?

On my linux box, the popup window lets me enter a pathname, and I
can just paste in the name of any of the various players that I have
installed.  But on OSX, the popup window doesn't let me type or paste
things in; it wants some sort of "choose" operation that I can't find
documented.