The broadcasted artist widget displays the artists most played on your radio over the last 7 days and is updated daily.
We use different services to compose our artist profiles and it is possible that some of your artists, although frequently broadcast on your radio, may not appear on the widget.
This can be due to 3 reasons:
The artist name entered on your songs is not correct. In this case, go to your Radio Manager under Library > right click on the song in question > Edit > Then enter a valid artist > Save.
The artist is recent and the artist file has not yet been created.
The artist is not present on the services we use to create the artist files.