Being pretty familiar with media consumption of Arabic language programming in the U.S., most are listening to programming from streaming, mainly sources from their home countries. As with a lot of foreign language programming carried on radio, much is block/paid by an individual, or group in that community trying to reach, successfully or no, that audience. This is especially true, considering 99% of people in the U.S. who are from MENA, own and use smartphones for not just consumption of media and entertainment, but communication back to their countries of origin.
But the fact is, just because it's on an AM station, doesn't mean any majority know it's even there, let alone listen.