Super song, played now and then by British youngster (5)
I believe the answer is:
sprog
'youngster' is the definition.
(I know that sprog is a type of youngster)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for sprog that I've seen before include "Infant" , "Kid" , "Child, colloquially" , "Child; recruit (mil. slang)" , "Baby (slang)" .)