I downloaded files that were uploaded by a training institute. It takes 2-3 hours to download the file each time and once it is downloaded (to my laptop) it has no sound. It is an mp4 format and I have tried multiple media players, checked to ensure my volume and theirs is showing as on/not muted. I have three different trainings to do from this and I've taken far too many hours simply trying to gain access 😞 Can someone help me figure out how to get this to work