Revolution Slider Arrows Not Showing

Hey there, getting an error with the Revolution slider, the icons aren't showing in the next/previous buttons. Instead squares are showing.

Preview site here:
http://www.dev-cadencedevice.com.php56-31.dfw3-2.websitetestlink.com/

Many thanks

Managed to get to the bottom of it. Adding the following code the navigation.css file fixed the issue:
@font-face {
font-family: 'revicons';
src: url('../fonts/revicons/revicons.eot?5510888');
src: url('../fonts/revicons/revicons.eot?5510888#iefix') format('embedded-opentype'),
url('../fonts/revicons/revicons.woff?5510888') format('woff'),
url('../fonts/revicons/revicons.ttf?5510888') format('truetype'),
url('../fonts/revicons/revicons.svg?5510888#revicons') format('svg');
font-weight: normal;
font-style: normal;
}