Android Instrumented tests fail when all run together

I am running Android instrumented tests using espresso.

I have a little more than 70 tests to be run which all click through different parts of my application.

When I run each test as a single test they all work and I get a green test result.

When I run them all at the same time (right click on the androidTest folder -> hit run) then some of them fail saying the view cannot be found.

In different runs different tests are failing. I think it might be that something is going too quickly here.

Do you guys have any suggestions on how to fix this? Thank you so much in advance!