Problem: Meteor 1.4 build with nginx SSL (Loop in Firefox)

I need help with configuration to run a Meteor build with PM2 and Nginx.

When I try to reach the site in some browsers the socket makes a redirect loop that makes a refresh of the page.

This webapp use SSL.

The nginx use a balancer with other 4 servers.

In this screenshot you can see GET XHR loop :

This is my nginx configuration: