I'm using OpenCube XFReader to QC MXF video files, and for some reason I just today began having a problem with the video image jittering. The video image jumps up and down slightly, when it's playing and also when it is paused. I don't understand why it's jittering, because it hasn't done this before, and I haven't changed anything. I'm not sure if this is an OpenCube issue or a display monitor issue. Any suggestions?