From 1922 to 1933, the Toronto Daily Star operated its own radio station, CFCA. Here’s a blurb from the October 15 1931 edition of the paper that advertised two upcoming musical soloists:
CFCA stopped broadcasting in response to legislation creating a national public broadcaster (the Canadian Radio Broadcasting Commission, which eventually became the CBC). The Star did not want to compete with a public broadcaster, and did not want to sink money into technological improvements during the middle of the Great Depression.
Google searches for Marie Baker and Elsie Thorpe-Brown turned up nothing – they appear to be lost to history.