Hello,
thank you for waiting us,
to solve issue with refreshing portfolio.
In your style.css file
(you can find it here \wp-content\themes\andy\style.css)
on line 2830 you have this code:
.portfolio_item_3{
width: 30.79%;
float: left;
margin: 15px;
}
We change width: 30.79%;
with width: 30.77%;
.
As we see revolution slider works fine when we refresh page, we test this in Google Chrome and Mozilla Firefox.
To change column width, click on dashed line and move her to left or right side (picture in attachment).
Cheers :)