FLASH: FLASH .wav files-not all equal?

[linque]

I subscribed to a sound effects site, downloaded several .wav files and then proceeded attempt to load several into Flash.  Some loaded, some did not..telling me the format was not recognized.  On the site, i'm informed that the sound files include the following variants of .wav..  PCM, Microsoft ADPCM, ACM, and MPEG-3.      Does anyone know (1) How to determine which format each file is and (2) whic format it is that "works" or imports and which does not??

             lin  (linque)