Created Unassigned: 'System.InvalidOperationException' occurred in Tweetinvi.dll [2038]

Hi,

I have been evaluating different C# twitter APIs, and Tweetinvi seems to be the best, but I am getting the above error consistently when trying to use Streams; for example using SimpleStreamExample() and similar methods in the Examplinvi project.

Can you advise what could be causing this?

Cheers

James