I'm trying to convert an .mp4, but it won't load in. I keep getting "An unknown error occurred. [CR:0x00000002]". I've tried renaming and changing the extension to .m4v, .3gp, .mp3, .mov. VLC seems to be the only program that will accept the file; however if I get that loaded in (.m4v file), my output is video only and no sound.