datagrid binding + refreshing page + sometimes shows empty

[dave]

Hi
I 'm binding data to datagrid in following way in page load event

if not page.ispostback then
bind data here ' calling function tht return dataset
end if

what happens is when i keep refreshing page for 10-15 times , its shows
blank datagrid after certain refreshes...
i ensured that viewstate is enable and also smart navigation is also true...
i m using vb.net and sql 2k.
can anyone plese help me to figure out whts going on? this has been driving
me crazy..
thanx in advance for help!!

dave