[Radio format] Frequency of programming interruptions (by DJs or commercial advertising)³ [AM/FM] Highest4 None to low - dependent on the provider; however, it is common that some stations will have DJs. Usually no advertisements on subscription services (DirecTV and Dish Network both claim to provide advertisement-free content). [Satellite radio] 
None to high - mostly dependent on the channels, some of which have DJs; most channels are advertisement-free because of the paid subscription model of satellite radio.