Hmmm this is a tough one...because if my spanish serves me right....
Pichanga is a dish also known as picadillo which usually consists of Ground Beef, French fries and olives. I'm sure he's referring to the As s.
Catanga is a beetle that usually resides in excrement or droppings. lol
so if i'm translating it right.....which I hope i'm not! lol....he's saying: Shake your as s that tastes like sh*t! lol jajaja
Knowing Calle 13, I wouldn't put it past him! He's always saying crazy sh*t!!!