If slick actually goes to the wrong line you could try rebuilding your tag file.
Did anything change just before you first noticed the problem? e.g. did you install a hotfix or an upgrade, did your machine crash, did you get a new mouse or video card? If it worked correctly for a while before it went wrong, you may be able to resolve it by deleting your vslick.sta file (with slick closed - and back it up first), then start slick.
Does slick set the position correctly when you step through search results or go to bookmarks?