Green’s Dictionary of Slang

(UK Und.) a voice.

1725		New Canting Dict. n.p.: squawl a Voice; as, The cove has a bien Squawl; The Fellow has a good Voice.
1737, 1759, 1760, 1776		Bailey Universal Etym. Eng. Dict. [as cit. 1725].
1830		Mr Mathews’ Comic Annual 23: Hark! I hear another voice: I must look out for squalls – that’s not Jerry’s pipe.