I’m in a creative field myself, no musician although I’ve always wanted to be, but my talents and abilities lie elswhere. Funny how the human mind works, I’ve experienced it myself, seemingly perfect things arriving in a dream. I’ve speculated that there’s some sort of subroutine, for the lack of a better word, running in the background of our brains, for creative types at least.
I think the deep relaxation of the dream state can sometimes allow a person to work out a complex matter that’s harder to do while the mind is awake and cluttered with thousands of random thoughts and other tasks.
I’ve occasionally gotten other insights or realizations while in that state. It’s an interesting subject, no doubt.