Caused by not calling `Engine::destroy`, as well as creating tracks/clips on the heap and not freeing the memory at the end of the test. Instead of creating tracks/clips on the heap, they are now made on the stack, similar to how the surrounding tests create its objects.
test-files and their MD5 sums go here 16a41b09841f6893c6a621f3e7c63692 emptyproject.wav