>The term derives from "link", a term for the cotton tow that formed the wick of the torch. Links are mentioned in William Shakespeare's Henry IV, part 1, as Falstaff teases Bardolph about the shining redness of his face:
"Thou hast saved me a thousand marks in links and torches, walking with thee in the night betwixt tavern and tavern." (Act III, scene 3)
ETA: Ah, already here, just not widely distributed.
You've just confused the concept with music added in post when that's actually what it'll sound like when fully deployed.
/s
The 17th century hardly classifies as "the middle ages".
It's not obvious to me that there could not have been link boys in say, 15th century London, which really was still a medieval period - they just need a torch or maybe even a candle - but I didn't find records of such a thing. It's possible that wealthy people in 15th century London just would not venture out alone at night in numbers to justify this trade.