I have exactly the same issue!
I contacted the tech support today and they told me my port is not open. which was true.
Which is weird, considering I have not changed anything on my network in weeks, and I only have this issue since a few days.
now I have opened manually the port on the router, but still no change. Support told me they still see the port is not open. I actually checked the port on the internet and it says it's open.
it streams nicely inside the network, but remote streaming is super slow. Best bit rate I saw was 500Kbps, my network has (just tested from the router) 98MBpmns down and 8,9Mbps upload. seems more than enough.
Now your message raises more than one concern...