From Salvatore Nittoli, »Vocabolario di varî dialetti del Sannio in rapporto con la lingua d’Italia« (Napoli, 1873), in which it is defined as a synonym of Zampognatore; NB: ➺ similar terms.
Sources
Web
Google books (Nittoli [Find zango [sic]: p.251; ➺ top of page: Zampognàro (NB: Note the first "a" (which is written upside down!) in Zɐmpognatore)]).