lip syncing issues with lots of different video help

[gsxturbo11]

Morning!

I'm sure this is a newb question but I've been working 2 days straight on this short video and have decided to ask for some guidance. The leadership of my company all took videos of themselves and sent them all to me to put in a video and sync to a song. I converted them all to the same frame rate of the lowest quality video clip which is 25 fps and put them in microsoft video editor and another open source video editor because I was having the same issue. They look perfect in the software but when exported to an mp4 720p at 25fps the sync is off for 20-30 seconds about a third of the way and then finally catches up.

This is my first time doing this and have read a ton at this point the frustration is emence and looking for some help! Thank you!

[ProWo]

Original video fps?
Why you convert to 25 fps?
You convert video and audio at the same time, or video only?
Many questions ....

[gsxturbo11]

There are 25 videos ranging from 25fps to 30fps and I read it's best to have them all converted to the lowest fps. The song is a 256 mp3 and the audio in the videos are muted. After I was done with everything I converted the entire file to 720p 25fps mp4.

[ProWo]

The song is a 256 mp3

Is this an audio track from a video? If yes, what fps have this video? Or is this a normal song track from an CD/DVD? In this case, why lipsync?
More info, please.

[gsxturbo11]

It's a normal mp3 from like a CD. Ya they are lip syncing to the song. In the editing program the lips are synced up perfect but once exported they are off.

[gsxturbo11]

I can upload it to dropbox if you wanna see it.

[johns0]

Just upload it here.

[ProWo]

I think it's some kind of karaoke show. In this case the video has to last as long as the music. That's the job.