When I move cursor in my listbox, a line is show at the top
of my form. That line is the same as the selected item of
my listbox. When displayed one time, that line never disappear.

FYI: This seems happen when the number of items in
my listbox is larger (but not more than 350 items).
The InterActiveChange event execute some lines of code.

Someone could explain to me.
Thank you.