Some Chorale members asked me why we pronounce our Latin as we do. The short answer is: because that's the way I learned it, and I am fortunate enough to be musically descended from a long line of well-educated and skilled choral musicians from the Westminster Choir College school of thought. There is a longer answer, that is summed up in this excerpt from a well-respected text by Robert S. Hines, renowned Julliard-educated composer, director, and educator in choral music.
Baba Yetu pronunciation guide! To increase the language flavor try pronouncing the "T"s as if they were in Italian: like a cross between T and D ... or pretty much the same way we say a T, but with no escaping breath.