Nearby MovieClips "shake" and "vibrate"

Question

I often have this problem but didn't really care about it
when it doesn't appear to be too apparent. But this time, it is
quite obvious.
There seems to always have a problem in some of my animations
when I have movements involved for clicking something. Say for
example, I have a button that will slide a banner downwards when
clicked, the layers or MovieClips beneath and around the sliding
banner seems to "shake" and "vibrate" while the banner slides. The
shaking and vibration stops when the animation stops.
Now, I didn't have this problem when I publish the SWF in
Flash(though I have this problem in the SWF at other times) but
when I load it in Flex, the movieclips around the moving movieclip
in the SWF file shakes. It looks as if the layers of movieclips are
"rubbing" against the moving movieclip.
Why is it this way? And how could I fix this?
Thanks!

Answer 1

anyways, in case not many people are having this problem,
just to show how this problem looks like, i managed to find an old
example that i have this problem.
go to
http://www.monvogue.com/weirdprob/myprofiler.html
and click on any of the names. when the name list slides away to
show the profile, look at the time shown at the top right corner.
it seems to "vibrate" when the list moves.
the name list and the time are two seperate movieclips in
flash.
The example that I have uploaded to show was made some time
back in AS2 with Flash 8. The animation was using the Tween class
in AS2.
Now, the present problem that I am having with another file
is an AS3 file that is made in Flash CS 3 as a Flex component. As
for the tweening in this one, I am using timeline tweening. The
tweens are simply the transitions of the label states. For this
one, the "vibration" only happens after I put it into Flex. It runs
fine on the Flash player.
I am using Flex Builder 3 beta 3.