I did run into something like this once. I have one suggestion. Make sure you have your current IP address on the whitelist. The bug could be the same as I am seeing but I have noticed a similar failure in the past when they added the whitelisting as being required. Although from memory making another key pair did not fix this. Still it seemed worth mentioning.

Another thought would be to look at the debug information. Press ALT+SHIFT+D together. Change the radio button to debug. Let the log run for maybe 20 seconds and then uncheck enable. This will stop new data from showing up in the window. Look for any lines that do not say success or that say failure. If it is related to the issue I am having the line would look similar to the line I have posted from more then 1 debug log from more then one failure. I don't know where the failure is but maybe one of the two will give you an idea why.