Apparently they had marching music which was fairly fearsome sounding with cymblas, horns and all. I found this advert for a sort of reenactment from 1999:

...Entire villages threw themselves to the ground at the approach of the Ottoman army. It was the Jannisary Band leading the way... Enlist Now in the Jannisary Band for Pennsic XXVIII (Lead the army of the best paying kingdom(s) into battle) Musicians, Singers, and Non-musicians are Welcome! (Horns & Brass, Percussion and cymbals, Chorus, & Standard-bearers) We teach you the music, the words, and the marching technique (one authentic 15th century song will be taught) You provide a red kaftan, yellow sash, and white turban cloth (scholarships available). We turn You into exotic, fearsome Turks to make the masses quake! There will be 2 practice musters at Pennsic, as well as 2 separate A&S classes taught to coincide with the group's formation. (This is intended to be a really neat, casual & fun experience). If interested contact us and we'll mail you an "enlistment" packet with detailed information, photos, and an audio cassette. Master Karl von Nord Mark (Ted Monnich)