Video Good Sound Off

I stumble upon Media Share after getting Direct TV hook up.  First I had no luck in using MS even though the Media Servers were present, I reset the DVR and that worked.  My question is when I play any movie from Media Server-TVersity the picture is good but after 15 seconds or so the sound tend to stop for a fast second and is not in sink with the picture.  Very movie I've tried, this happens.  Have other people had this problem? I was wondering if there was some copyright protection with Media Share that causes this.