At my university, the curricula in various areas of engineering are heavily structured, with very few electives. While 120 credits are required for graduation in most majors, more than 120 credits are required in engineering. The only “break” that the engineers get from the math/science/engineering courses is with the distribution requirements (humanities, social science, writing). I think they have 4 elective courses in a 4-year time frame.
I have seen transcripts of music majors at my university. They are typically full of music courses, with one course outside of music per semester.
Both music and engineering courses are very demanding, in terms of time required.
It would be genuinely impossible for someone to double major in engineering and music and graduate in 4 or 5 years. It might be possible to do it in 6 or 7 years. The OP’s daughter should look into the requirements of both majors, and see whether it might be better to drop the idea of a double major. I agree with mathmom about this.