Scroller bug? #top gets 'lost'

[Dylan-30]

Any ideas/pointers - I have a scroller that, depending on the events
on the page scrolls to a specific #point_xx in a div.

First time the page runs everything is fine and the scroll div sets
#top correctly.

The page is then reset (not refreshed - there's someone else's 'reset'
scripts here) and on each .ScrollTo the #point_01etc. (#point_n)
doesn't appear at the top of the pane - instead it's about a third of
the way too far up.

Not sure where to start checking out - any pointers would be great.
Unable to post full example as client code in progress :(