Nine Inch Nails’ Trent Reznor — who is also chief creative officer of Beats Music — is working on a secret music project with Apple, according to a recent interview in Billboard. When asked if the project was about music delivery, Reznor said, “It’s in that world.” He also noted that Apple “expressed direct interest” in Reznor designing products for the company when Beats was bought by Apple. Apple’s interest…