I need to locate my notes that should have the mekor in Kovetz Teshuvos where Rav Elyashev paskens that there is no such thing as intellectual property in halacha.
Your quote was by a third party who takes a strong pro-music producers position, as evidenced through his sefer, as he understood Rav Elyashev. It was not Rav Elyashev himself giving his position.
And my request for your source on Rav Elyashev was not in the least bit rude.