mplayer(1) -nocache -afm ffmpeg
movie player
       Turns off caching.
-afm <driver1,driver2,...>
       Specify  a  priority  list  of  audio  codec families to be used, according to their codec name in
       codecs.conf.  Falls back on the default codecs if none of the given codec families work.
       NOTE: See -afm help for a full list of available codec families.

          -afm ffmpeg
               Try FFmpeg's libavcodec codecs first.
          -afm acm,dshow
               Try Win32 codecs first.
source manpages: mplayer