The "monk" clue is a bit strange - monks are by no means the only people who sing Gregorian chant (the best answer is probably cantor, although that has too many letters obviously). I was quite confused what answer the quiz wanted for a while - maybe a better clue might reference monastic musical liturgy or something.
Saw ____sonic, knew this was about music, and couldn't get past JJ Fad's Supersonic. Still haven't read the clue, didn't matter that super is five letters.
Can "disk" be accepted for "disc"? It doesn't fit the chain, but I've seen it spelled "disk" often and it might help other people who spell it that way.