I've used Movie Maker plenty of times and never found it inconsistent during playback.  If a video image coincided timewise with a certain part of a song during one playback, it would do the same thing during a second and third playback.  That's all changed recently.  The change showed up right after Windows 10 was installed on my system -- tho' this may be a coincidence since I had gone a while without using Movie Maker until recently.  (This is probably also the first time that I've tried to make a Movie Maker video on my new ASUS "republic of games" computer, but that may be a coincidence, too.)

In any case, now, when I cue video to start at a certain point in the song that I'm using, I can play the video back and get perfect results the first time, and then the next time (without having made any changes to the file whatsoever) the video and the song will no longer be in perfect sync but will be off perhaps by as much as 2 seconds.  I can run the thing again and get different results, sometimes showing things back in sync again, sometimes showing things off by another small random amount.

Can anyone tell me why this might be happening suddenly?

Thanks!

Brian