Is it
1.1 "it doesn't matter if you hear it on rap tracks"
1.2 "it doesn't matter if you hear it in rap tracks"
Would it be different if I use "song" instead?
2.1 "it doesn't matter if you hear it on rap songs"
2.2 "it doesn't matter if you hear it in rap songs"
My gut feeling says "on" is correct, with 2.2 allowed colloquially