Full width layout row jitters on mobile

Hello,
I am using Page Builder with Virtue Premium Theme and it is a great plugin.
I have made a full width row with background image and some content in it.
I have noticed, on my mobile (iphone 4) the row is jumping a little up and down when scrolling.
When I change the row width to standard, the jumping disappears.
Here is the video of the jumping, hope you can see it:
https://www.dropbox.com/s/wqrkpj8fnwpovuw/Capture_20151121.wmv?dl=0

Then I made a full width row in html with themes row “kt-custom-row-full-stretch” and the jumping also disappeared.
Have you any idea what can be the problem maybe?
Thanks in advance, Gabi