MYSTERY SOLVED
All day long I've been aware of a slight ringing in my ears. It was almost imperceptible, but it was there. Nice, I thought, I'm turning into one of those people who slowly go deaf as I'm simultaneously driven mad by tintinitis.

And then I looked out my office window, and all was explained. They're back.

Not that that doesn't mean I still won't be driven mad and deaf, but at least it won't be because of a medical condition.