People can't access to my website eventually with smartphone

I have a Wordpress site with a lot of traffic http://goo.gl/CmCEBq

Some people claim that they can't access to my website sometimes with their smartphones by wifi (it happens to me too).

The website not load, that happen: - White screen with progress bar - Mobile navigator show a connection time out - If the people try to access by facebook app, come back to Facebook again.

but if I change to 3G network, can access without problems.

I asked to the people and this happen in all countries, and devices.

This issue happen intermitent, because if you try again many times, finally can access to the website.

The website is hosted in a cloud server, with a load balancer.

I tried many possible solutions like: - Change DNS - Deactivate plugins - Reduce content on the website to minimice the load

Can somebody know whats it the problem?