Syag- Unless your son’s rav is a musmach of YU (kidding) or relies on the daas yachid opinion of the chelkas yaakov, there really is no reason to be meikil regarding listening to ANY music unless one’s parnassah involves music or it would make one depressed to not listen.
C”V for you to assume that what I wrote are my “feelings.” Aderabba, I rarely answer halachic questions on the cr because I’m certainly not ra’ui lifsok yet. In this case though, I have learned clear mekoros found in the works of the Aruch Hashulchan, Rav Moshe, Rav Ovadia zt”l and most recently, Rav Belsky, who are all very clear that music is assur in all forms (including acapella except if there is no digital enhancement to the voices), since listening to music is a joyous activity and could probably lead to dancing or use of kli zemer. I’m more surprised than offended that you’d accuse me of dishonesty. neseiv sefer venechzi.