What do you mean by the SSH Connector Test hangs. Typically the Test button will generate some type of error response if these is a failure. Sounds like there is a connection issue.

A general note that firewalls and other network security appliances in most modern environments are able to inspect and actively block SSL connections for security reasons. If any of your applications are in the Cloud you must assume there are network appliances inspecting the traffic even if you are not actively aware of them.

In some instances actions by these appliances to block the connection will be interpreted at the application layer as a connection failure but many times the actual connection error messages (if there are any) will be also be blocked so the application may just appear to hang.

SSL connections are typically made against legacy machines which may not adhere to modern cryptographic standards and these are where we typically see these issues.

Often the only way to 100% confirm the traffic is being actively blocked is through a network analysis using tcpdump or a similar tool.

In the absence of evidence just ensure that all your endpoints are up to date with security updates.