The Band's Visit Question

I was recently on an airplane (don’t ask how recently) and I got a chance to viddy the absolutely, jaw-droppingly horrorshow flick The Band’s Visit, starring Sasson Gabai and Ronit Elkabetz. During the film, when Gabai’s character explains that he plays classical music, Elkabetz’s character replies with a question that the subtitles translated as, ‘What, you mean like Um Khartoum?’

My question is, what is ‘Um Khartoum,’ or whatever it was she was referring to? I have searched for this song to no avail, but have never found it.

And, to launch off that topic, what is there to be said about Arabic classical music in general?