Bad testing environment?

Has anyone ever filed a report to CB for bad testing environments? When I was taking my subject tests today there was a constant sound disrupting my focus. It sounded JUST like a boiling kettle with the high-pitched whistling noise. At one point, I think I started to get a little bit of a headache. The proctor tried to find the source of the sound but just gave up and said that we had to start the test. Is this a good enough reason to file a report to CB? What actually happens if I file one?

If you file one they will likely let you retake at no charge.
You should call them on Monday.