Actually I can't english well, so I copy this Question from the same problem on me.
Hello, I've been using SeeMusic for a while, and this problem has happened on and off. I'm using Mac. After exporting, the saber in the final video sometimes abruptly "restarts," causing it to go from one position to a completely different one the very next frame, instead of gradually and smoothly moving as it usually does. Is there a way to fix this?This happens with any of the three saber presets included with the software.