Socket issue with Uploads

I have a project where I had built a simple uploader to the local meteor server. It worked fine on my local machine and on the cloud server it was deployed to. Most beta users are able to upload with no issues. However, I have a user in South Korea who gets socket issues when trying to upload. He has with Chrome and tried with both a US based VPN and via his Korean IP.

I’m wondering as a more general question has anyone seen anything like this? We are moving the uploads to S3 using slingshot so this wont be an issue moving forward. I’d just like to have an idea of what the issues is in case I run into something like this again.

Meteor actually has some of the issues by themselves: which might be an interesting read.