Icon blocks not appearing/disappearing on iPad

Hi Guys, we’ve added 2 icon blocks http://gd3.geneticdigital.co.uk/ on top of a fixed image (very similar to your demo site), about 2 thirds of the way down the page. They which work perfectly on all platforms except the iPad. If you scroll the page from top to bottom without stopping you see the background image but not the icon boxes on top. If you do this again from top to bottom or bottom to top and stop the page scrolling when you seen the background image, the 2 icon boxes appear. This means when visitors are viewing our homepage, they will not see the icon boxes unless they stop exactly on the background image. Is there something thing that can go into the custom.css that will force these icon boxes to appear?

Thanks