HDMI Audio connection/disconnection

When VLC is open, and an HDMI cable is plugged/unplugged VLC ceases to play any audio until it is quitted and restarted. For instance I can be playing a video with sound and then disconnect the HDMI cable to an external video&sound system; at that point video continues to play on the primary monitor, but the sound will stop. It would need to fallback to whatever the currently available audio output device is, in this case the laptop's onboard speakers. Another example is if I am playing a video on the laptop normally (onboard sound) and then connect the HDMI, audio stops. In that case it should start using the HDMI audio. Video, again, is ok and can be dragged onto the newly connected display without problems.

I don't expect it's a MacOS issue, since other applications, for instance video/sound playing from a web browser exhibit proper behaviour.

I'm using OSX 10.6.8, VLC 1.1.12 Hardware is a MacBook Pro connected to an Onkyo HTX-77HDX receiver/stereo that passes HDMI video through to a projector (Epson 8350) All HDMI connections, though there is a MiniDisplayPort-->HDMI adaptor at the laptop connection point.