1080 video with no sound?


i have a few 1080p movies with 5.1 digital and the video seems to play fine but wont play the audio

anyhelp ???

More info needed. 

How are you playing them (directly from hard disc, via network shares or media server)

What type of files are they.(codec and container)

What are using to play them on and how do you connect to the player.(composite, component, hdmi)