Why does site "flash" with each page reload

[dwzemens]

I have developed several sites using the StudioPress Genesis framework. My most recent site "flashes" and seems to reload the images each time I move from page to page on the site. The header image reloads each time rather than transitioning smoothing.

Here's the site that flashes:

http://stjoesworkshop.com/newsite/

Here's another site I did a few weeks ago that does not flash but rather loads pages smoothly:

http://www.joannaforrochester.com/

It's like the one site does not cache the images and there's a forced reload each page view.

Can anyone help me out understanding why this is and how to avoid it? Thanks!