.mov no sound in movie maker

i imported one of my .mov files so that i can trim a part of the video.  i was able to trim it nicely, but i can't hear any sound.  i saved the result of the trimming hoping that the new file includes the sound (was thinking maybe movie maker can't play the sound, but can save the original sound file of the video and i'll be able to hear it if i play it on another program).  but the new file - the "trimmed" file - has no sound either!  i played it in quicktime.  went back to this project in movie maker,  tried turning up the volume to the max under the"edit" tab , but i still can't hear any sound.  my laptop's volume is at max too.  my original file has sound, i played it in quicktime.  i'm using windows 8.  please help..thanks..