I'm a guy who plays several instruments and isn't afraid to play each of them in a variety of keys. That said, apart from strange room resonances or something rattling around in the room or inside the speaker, it shouldn't make one iota of difference what key a particular piece of music is being played in when it comes to hi-fi reproduction.
Notes, keys, and questions.
I am not a trained musician. I cannot tell an A-Minor from a doe is a female deer. I hear loudness, instruments, harmonies....musical generalities translated into vague verbal terms. No issue with it other than a curiosity into how others, especially trained musicians who read notes like I read books, "hear" music. For instance. "My system handles B-Major much better than D-Minor." Does a trained musician translate what they hear into defined notes and keys? Whereas the majority translate it into words shaped by experience and/or general industry assumptions. Or is that even a reasonable assertion?