Resharper MSTest unit tests hanging when they finished

I have the problem that our unit tests are working without any issues, when they are run in the VS test runner.

When we are using the Resharper test runner it seems that the tests are finishing fine but you can pretty much see that when the test finishes the whole VS application freezes (the length seems to depend on the system and on the unit test but always between 2-30 seconds). Is there maybe a setting that we can disable to make the tests run as smooth as in the VS test runner? In my case the Resharper cache is already on a Samsung 960 EVO SSD and I still experience that kind of lag.

Video of the situation: (when one test finishes and another one starts you see exactly that it is not responding to any actions - and that is the case for the whole VS application):  https://www.youtube.com/watch?v=I3qp0rptTOU&feature=youtu.be

The behavior seems to occur in multiple versions (2016.x, 2017.1 and 2017.2).

 It seems to be related to the console output - If the output is disabled there seems to be no lag.