I just want to point out some of the issues about listening to non jewish music. before I begin I just want to mention that I am not referring to every singer, but to the majority.
a. MOST secular singers do not have proper morals. they spend there lives singing so they can become celeberties. once gained this title they will use it[title] to do the wrong this. so why should anyone, jewsih or not, want to support(by listening to their music) these singers?
b. these people are not worthy of admiration, but it is assur min hatorah to be admiring goyim. if you listen to non jewsih music, you may come to admire the singer, and this is prohibited.
c. additionally, there really is no reason to have to listen to such music. there is plenty of different types of jewish singers and music. anything and everything in the jewish music world can be found. so y not go and support you fellow jewish brothers and sisters who sing to praise H-shem, and help uplift others, unlike non jewish music, which focuses on physical aspects