Skype drops calls on connection

[jimmyeao]

We have a couple of these installed now, and planning on more. The device account is an office 365 account in the cloud. We can use Skype between the screens, but when calling a user who is remote, the call connects, no video or audio then drops a couple of seconds later. Not sure where to being with this one. Does it require specific port forwarding or URL whitelists creating?

Thanks