If you are running your show using CD+G songs, you should be familiar with silence detection, which allows to skip silence at the beginning and at the end of the song to make the show go smoother and faster. However you might not know that the same option is available for MP4 songs — you need to enable it in Settings / KJ.
Now Siglos will scan all video files are remove silence at the beginning and at the end.
Please remember that skipping instrumentals is only available for CD+G files.