I see the dilemma.
Something just occurred to me. When you're asking for direction, it's important to ask the right way. It's easy to force God into a box if you ask the wrong way. "Should I take History in some form along with my major?" might be the reason you're not hearing anything solid. It might be the wrong question. Maybe try other questions such as, "Should I take anything else with my major, or devote everything to Music?"
Another point: Let's say you decide on Music solely. Once you get into the program, if it's really what God wants you to do -- and only that -- then I'd expect the History interest would fade over time. But if God did want you to add History in some form, then I'd expect the drive to do something along that line to increase gradually over time. I know that's happened to me a lot, when God's speaking but I'm not necessarily hearing all that well: I'll start down a path I think He wants me to travel, and in a month or two or whatever, it becomes plain via the Spirit's prodding that my choice was wrong, and I correct. Kind of like the first moon shots where the travel paths looked like the teeth of a ripsaw -- constant corrections, and often some pretty wild ones. But they eventually made it. We're imperfect. We hear imperfectly. So we zigzag through life, just like those moon shots. God won't forsake you if you head down the wrong path, or don't take one you were supposed to take. He knows your heart's right. I think he'll give you a nudge and say, "Nope, go this way."
Stay loose, keep listening.