After this killing Aristasura pastime took place which is described here as
“krsnenadbhuta-karmana” (S.B 10.36.16)
This is wonderful pastime of Lord killing this Aristasura demon.
“kamsayathaaha bhagavan narada deva-darsanah” (S.B 10.36.16)
After killing Aristasura Narada muni comes to Mathura playing his Veena
“Naradmuni bajaye veena radhikaraman namane”
Narada muni veena, veena Narada muni, so when he comes to Vrindhavan Narada muni is because veena he plays everywhere and he sings glories of Rad