I don't know why, but the output of a video that has 23:40 seconds length got down to a 34 seconds length after interpolation. (The audio is accelerated also)

It keeps doing it no matter how much I try step three.

I used the mode 3 (Adaptive record timestamps) at x2 interpolation. Any clue to what could be?

That is strange, perhaps the application is not being able to correctly decode the video. Does Mode 4 also do this?