"Frames" window scrolling by itself

[i-tietz]

Hi there folks,
I have two movies open in the same window. I copy frames from one movie to the other. Whenever I "come back" to the target movie, the frame list shows me the same - some scrolling happened: The current frame is always right at the bottom of the window ... by the way: No, the current frame is not the last in the movie.
Strange thing: I go back to the movie that I get the frames from, and everything is just the way I left it - no scrolling happened while I was "away" ...

How comes? Is there a rule I'm missing that applies to one movie and not to the other?

Edit:
Correction: In the other movie the current fame is always at the top of the "Frames" window ... at least better than at the bottom ... why this different behaviour in the two movies?