Sounds like you simply have the wrong video source selected. While streaming, press OPTIONS - Video Select.
I wish it was that simple. My issue is, while streaming on the Internet radio source the on screen display doesn't come up so hitting option does nothing because the display is not up (like it does when I am on the cable, Bluray, tuner source when I can pull up the onscreen display and hit options and go through the the options like setting the video to TV while listening to the tuner).
Any other suggestions or am I misunderstanding your suggested fix?