Social icons dissapear

Hi,

my website is:

http://www.drehbox.de/wp-test/

The following only appears in chrome browser (testet under windows).

1) Under Kontakt (right above the footer) There should be facebook and vimeo icon next to the xing icon. And it just appears on hover. Why?
I used a column and added shortcodes
[icon_bar icon="icon-facebook" link="https://www.facebook.com/ARISDA.Filmproduction/" social="facebook"]
[icon_bar icon="icon-vimeo" link="https://vimeo.com/user4000995"  social="vimeo"]
[icon_bar icon="icon-xing" link="https://www.xing.com/profile/Aris_Bibudis"  social="xing"]


2) Additionally, there is just the xing icon in the footer section, although I added the correct links to Social-General (again: facebook and vimeo).

Any solution?


ThX

A. Bibudis