modifying a listbox which id bound to an sqldatasource

greetings. i have a bunch of listboxes which are bound to SqlDataSources.

I am trying to add items to the listboxes and automatically set certain items to be selected. No matter how many times I change the selected value, or add new items, the sqldatasource is the only thing that can control the data in the listboxes.

any ideas?

thanks in advance!