What is more proper to say:
What kinds of music you don't like?
What kinds of music don't you like?
Can you please explain why?
"What kinds of music don't you like?" is the correct one.
A simpler way to understand this is, consider "do" in place of "don't".
The sentences are:
"What kinds of music you do like?"
"What kinds of music do you like?"
The second one is correct, right?
It's the same way for your question.
You can say "What kinds of music don't you like?" But I would usually phrase it as
What kinds of music do you not like? / or What kinds of music do you dislike.
The sentence "What kinds of music don't you like?" sounds like a rhetorical question suggesting "You seem to like all kinds of music!" And not expecting an answer.
As there is a good word "dislike", I'd use that instead.