I have some old MP4 video's that have a problem with playback. I just switched to an Mac Studio moving out of the Windows world. The problem these files have is they play on some on my loaded players, Infuse, VLC, Quicktime but with only sound on my main player jRiver Media Center 30. This is not a new problem. This is the reason why I had several players loaded on the PC. I asked about this and was told that the best thing to do is covert them to AVI, MKV, etc. I have been looking at utilities the one in the Mac App store looks good but is limited in it only converts one file at a time. Any suggestions?