Hi
I haven't seen this fault before!
But I think I can see what you mean.......The clip remains in the same position on the timeline but the contents appear shifted so the clip jumps in time (or so it seems, but not sure if it is forwards or backwards) .
If the clip actually jumps forwards in time then it must finish physically in a different place on the timeline. Your video doesn't show the right hand end of the clip so it's not possible to see this. Jumping the other way i.e. towards the start of the clip might be more logical if you have trimmed the the start of the clip and it might be shifting in that direction. That doesn't seem to be the case. I can't deny it seems to be doing something.:blink:
However, I can't reproduce this effect in VP 8.84 using a similar set up as your example. I cant get it to slip either forward or backward when I add an Exposure effect. To check for any movement I have set the red cursor to a particular point in the clip (Where white boat is just passing the blue boat) so it appears in the Clip Preview window but both before and after the effect is added this position remains the same.