Many years ago when doing my Grade 4 on flute (the good old days), I had about 10 bars left to play on one of my pieces and everything was going fine (well, fine by my standards, anyway) until there was a huge sudden gust of wind from one of the very top windows which proceeded to blow all my music off the stand! Fortunately, I had memorised the pieces (I think everyone does with pieces that they practice loads anyway) so was able to get to the end of it fairly calmly and accurately.
Anyone else got any stories of weird and random things that have happened to them in music exams? The pieces, examiners, instruments....whatever!