Not loading map (only when refresh page)

Hi,

Great visual, great map.

After some days trying to solve this problems, I asking for your help.
The map only appear when you refresh de page, it neve loads the first time.
What is missing?

Website: http://www.oceanscan-mst.com/contacts/

Last plugin version (I already delete and instal again)
I check the API and is all active and going well.

Can someone you help me?
Thanks in Advance.