here vvvv is a bit lacking on comfortable multioutput settings.
Filestream will do that but can be tricky at times, very tricky others. First of all .wav files can be encoded in many different ways, be sure your .wav files do work with Filestream
Then if you use a 5.1 card or similar (as I did) … well first of all, if you can get a multi channel USB card. But if you do want to use a PCI/internal card of that kind take into account the driver and its relative control panel. Usually these cards will not activate channels as long as there is nothign connected to it. Also I ve encountered a weird behavior where if I didn t send anything to the front outputs then rear and subwoofer were not activated. This costed me a few days of head scratching!
Have a look at Bass Audio as well but I ve never tried my self.
Good luck (and no afaik VLC does not support that inside vvvv)