[firedrake] Firedrake test script not advancing

Dear Firedrakers, I've just installed Firedrake on an Ubuntu virtual machine, and I'm finding that the firedrake test script seemingly stops advancing (sometimes at different points in the tests). By `stops advancing' I mean `stays on the same test for at least an hour'. I've attached the console output for a couple of attempts running the test script. Is there something I'm doing wrong, is this a bug, or is it an issue with the virtual machine? (Or something else?) Thanks, Owen