formview problem updating data

Very strange behavior with formviews on  For some reason, if I declare the SqlDataSource on the page source but then do the binding of the SqlDataSource to the formview in code behind, no error are shown but the data does NOT get updated on edit.

So instead of doing this in code behind

summary.DataSourceID = "summaryDS";

I need to do this on the page

<asp :FormView ID="summary"

A previous problem I encountered with formview