screen flicker using .show()

screen flicker using .show()

Hi there
 
I am getting screen flicker during the .show() method under Firefox 3.6.
 
This doesn't happen in FF4, Chrome, Safari and IE8.
 
I have the div table size of fixed value (so no vertical resize needs to be done) of the divs (a list of 20 table items) operated on by the .show() (and .hide()) but still I am getting very bad screen flicker (the whole screen goes white for a second (or even two...) before refreshing which gives users a seriously bad headache).
 
This flicker only seems to happen when performing operations at the bottom of the screen, elsewhere (such as the left side controls positioned at about halfway down the page) no flicker at all occurs! 
 
This is driving me mad, and reading over the web I see significant problems with this issue, but no solution.
 
Anybody any ideas?
 
Many thanks.