Espresso test fails with NoActivityResumedException often

I have a strange error that occur many times when running espresso tests. After a couple of successful test runs the tests starts failing with following exception:

android.support.test.espresso.NoActivityResumedException: No activities in stage RESUMED. Did you forget to launch the activity. (test.getActivity() or similar)?
at dalvik.system.VMStack.getThreadStackTrace(Native Method)
at java.lang.Thread.getStackTrace(Thread.java:580)
at android.support.test.espresso.base.DefaultFailureHandler.getUserFriendlyError(DefaultFailureHandler.java:82)
at android.support.test.espresso.base.DefaultFailureHandler.handle(DefaultFailureHandler.java:53)
at android.support.test.espresso.ViewInteraction.runSynchronouslyOnUiThread(ViewInteraction.java:184)
at android.support.test.espresso.ViewInteraction.doPerform(ViewInteraction.java:115)
at android.support.test.espresso.ViewInteraction.perform(ViewInteraction.java:87)
at com.mycompany.testapp.ui.views.MainActivityTest.WhenNavigatingToSecondViewThenCorrectViewShouldBeShown(MainActivityTest.java:64)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:45)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:42)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28)
at android.support.test.internal.statement.UiThreadStatement.evaluate(UiThreadStatement.java:55)
at android.support.test.rule.ActivityTestRule$ActivityStatement.evaluate(ActivityTestRule.java:257)
at org.junit.rules.RunRules.evaluate(RunRules.java:18)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:263)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:68)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:47)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:231)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:60)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:229)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:50)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:222)
at org.junit.runners.ParentRunner.run(ParentRunner.java:300)
at org.junit.runners.Suite.runChild(Suite.java:128)
at org.junit.runners.Suite.runChild(Suite.java:24)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:231)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:60)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:229)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:50)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:222)
at org.junit.runners.ParentRunner.run(ParentRunner.java:300)
at org.junit.runner.JUnitCore.run(JUnitCore.java:157)
at org.junit.runner.JUnitCore.run(JUnitCore.java:136)
at android.support.test.internal.runner.TestExecutor.execute(TestExecutor.java:54)
at android.support.test.runner.AndroidJUnitRunner.onStart(AndroidJUnitRunner.java:228)
at android.app.Instrumentation$InstrumentationThread.run(Instrumentation.java:1853)

I have a simple app with navigation to pages just containing text at this point, and the test should navigate to each page and identify this text.

@RunWith(AndroidJUnit4.class)
@LargeTest
public class MainActivityTest {

@Rule
public ActivityTestRule<MainActivity> mActivityRule = new ActivityTestRule(MainActivity.class);
private MainActivity mainActivity;

@Before
public void setActivity() {
    mainActivity = mActivityRule.getActivity();
}

@Test
public void WhenNavigatingToFirstViewThenCorrectViewShouldBeShown() {
    onView(allOf(withId(R.id.icon), hasSibling(withText(R.string.first)))).perform(click());

    onView(withText("This is the First View.")).check(matches(isDisplayed()));
}

@Test
public void WhenNavigatingToSecondViewThenCorrectViewShouldBeShown() {
    onView(allOf(withId(R.id.icon), hasSibling(withText(R.string.second)))).perform(click());

    onView(withText("This is the Second View.")).check(matches(isDisplayed()));
}
}

All tests are executed by gradle script, starting with removing the previous app and test api, before installing it again. To ensure clean environment. The log indicates that uninstallation has been successful. Then deploying the new app and start running the tests. Now they fail.

If the tests have failed, it's not until I manually remove the app and the test api from device that I can get successful tests again. But only for a while until the same error occur.

Why do I get NoActivityResumedException, I can't find a good example of what it is and when it occurs. It seems like the Before method isn't run before each test according to the log:

Did you forget to launch the activity. (test.getActivity() or similar)?