Earlier quoted context omitted.
Try MPlayerX for OSX, I prefer it over the new VLC.
I tried MPlayer OSX once, and found that it turned my mac's volume up to max everytime I played a video. Sorry guys, endangering my audio equipment is terminally bad QA in my book. No thanks.
I would tell you how but I don't use OSX. Surely someone else can tell you, or you could learn yourself. It's worth learning how to use mplayer, if you are serious about audio.