How many times do we have to do this?
First of all, if there is not a single Gemara which says a certain thing is frowned upon, you will have a hard time convincing me that it is problematic. And certainly if it is not mentioned in the rishonim or in the Shulchan Aruch. So please, somebody, show me a source that says that ‘converted’ non Jewish music, or even the real thing, is inherently a problem.
Second of all, there are sources that indicate the opposite. The Gemara in Chagigah says that Acher went off because his mother used to listen to the music of the Greeks. But wait, Rashi goes out of his way to explain that the problem was that she was violating the takanah not to listen to any music out of mourning for the churban. Why didn’t he just say of course, the goyishe music has a ta’am that is metamtem the lev??
Also, let me quote myself, from about 8 months ago, regarding using non Jewish songs in davening:
“The Mishnah B’rurah (53 s.k. 82) says it is mutar unless the song is meyuchad specifically for mass. Therefore if it is a song that is sung both outside the church as well (l’havdil, parallel to the tunes chazzanim use for l’cha dodi and mimkomcha etc., not the actual nusach) then it is fine. He is quoting a Bach (Shu”t Bach haYeshanim 127) and though I don’t have one offhand I distinctly remember that the Bach’s reason that such a song is problematic is because of uv’chukoseihem lo seileichu, (which applies to anything meyuchad for avodah zara, not because of any inherent tumah) which does not apply to regular songs of non Jews specifically because of what I mentioned above that music is a chochmah, and he quotes the gemara in Avodah Zara that “lav minayhu gamrinan”, i.e. the goy didn’t “make it up”, he just thought of it.
The same halacha is found in Birkei Yosef of the Chida, if I remember correctly it’s in 560 by the g’zeirah not to listen to music after the churban.”
For the rest of that discussion, see http://www.theyeshivaworld.com/coffeeroom/topic/non-jewish-jewish-music/page/2