This seems bizarre and I have a degree in music! I wish I had some good advice for you but I suppose you could go and politely ask the objective of the course musically. In similar situations I have refused to take part and said its private. Never giving any reasons or even letting them know its triggering just that I wasn't happy sharing private details in a situation like this. Since no one has any idea have have problems I always got away with it with people presuming I was either attention seeking by not doing it or just a bit wierd! Both preferable than them knowing the truth! If you are more open you could try a quiet word with your tutor, but I think a good approach may be to ask more about the musical objectives. Good luck with this and let us know how you