That was quite odd. I went to Music again - I should explain, the timetable was changed three years ago so that all lessons are double periods, 100 minutes long. So there are only three periods in a day, and there has long been a fortnightly timetable. This has a great benefit for Music because, for practical work, it takes some time to co-ordinate a classful of pupils and explain what they're going to do, show them and then go around the classroom and practice rooms, helping and making sure they have got the idea. However, the demands of the curriculum mean that, for Year 9 pupils, who have not yet chosen their GCSE options, they can only have one long music lesson a fortnight. So I go in weekly, and help with two different classes.
So we were doing the same music, Katy Perry's Firework and Pachelbel's Canon, as I mentioned last Thursday. And I'll explain the link - they both have a fairly simple repeated base melody. Next time, they will be working on the Pachelbel again, each pupil playing a different part within their own small group, and they should be able to play the first part by the end of the lesson (not the whole thing. It gets jolly fast). The tune in the bass is C, G, A, E, F, C, F, G. The second C is the octave lower than the first.
So, that was quite straightforward. And afterwards, I got in the car and drove over to Beccles, because I left my purse behind and was going to retrieve it. After I'd gone about a mile, it dawned on me that I could hear that Canon tune. I listened carefully. I had not recorded it on my phone, there was no possibility that it was playing somewhere, but I was not singing it in my head, I wasn't consciously thinking of it at all. And it was definitely the sound of a piano, not a voice. I listened. And after a few minutes, there were a few mistakes, such as a repetition of the F, C before going on to the F, G. I could hear it all the way over to Beccles, ten or so minutes away. More variations - or mistakes - crept in as I drove along, but there were still the same notes, no D or B creeping in, the same pitch, the same tempo.
Once I reached Beccles and was looking for a place to park, I didn't think of it any more, and by the time I did, the sound had vanished. I occasionally get tinnitus, though not badly, and then it goes again, and I suppose it's a form of that. It was more interesting than unpleasant and I'm not concerned about it. It's just odd, that's all.