"Duts" are often used in marching percussion to keep the section on the same page, but sometimes drummers will add some fun to it with vocals.

Videos used are listed below
Miles Kenobbie - Blue Devils 2017 -    • Blue Devils 2017 Snare/Quad Cam - Mil...  
Reuel Camacho - Bluecoats 2015 -    • 2015 Bluecoats quad cam - Rue Nani Nahh  
Elijah Jones - Blue Devils 2019 -    • Blue Devils 2019 - Tenor Head Cam - E...  
Miles Kenobbie - Blue Devils 2016 -    • Blue Devils 2016 Quad Cam - Miles Ken...  
Matt Allen - Bluecoats 2016 -    • Bluecoats 2016 victory run snare cam ...  
Joseph Grippo - Blue Devils 2017 -    • Blue Devils 2017 "Metamorph" Victory ...  
Mando Gaucin - Bluecoats 2016 -    • Bluecoats 2016 Quad Cam - Finals - Ma...  
Miles Kenobbie - RCC 2019 -    • RCC 2019 Quad Cam - Miles Kenobbie