I'm attempting to use either Showoff.io or localtunnel on my Macbook Air, to make a Rails app running on a Vagrant VM available for testing on external devices. Other uses with identical hardware on the same network are able to do this successfully using the same Showoff credentials.
On my machine, there is a tremendous delay, usually leading to a timeout, before content is served. Using curl, I can see that the DNS resolves almost immediately, but there will be a delay of several minutes before I see a request reach my Rails logs. There will then be another simliar delay before I see content in my browser, and typically only the base HTML is successfully delivered. Subsequent requests for the CSS/images/JavaScripts typically timeout as each of these requests is subject to similar delays.
I am not running a firewall, and my Macbook is more or less set to factory defaults. I've tried this on two different Internet connections, one wired and one wireless. The symptoms are the same for my paid Showoff.io account, a free 5-minute showoff.io account, and a free localtunnel account. I'm completely out of ideas on what I could possibly try next to diagnose this problem.
Can anybody suggest a possible next step for figuring out why I'm experiencing this delay or how I could fix it?