Nvidia 8400GS HDMI Cant get TV Output

Using Vista 32bit with Nvidia 8400GS (DVI + HDMI outout), connected DVI to 20" monitor no problems, but trying any form of connection through HDMI to HDMI to my Toshiba 37WLT68 LCD I cant get an output, only a black screen - I know there is at least some form of connection as when there is no source my TV displays a blue screen. Doesn't do dual view, cloned view or single view to TV. Tried recent drivers and the latest Beta but still not happening.

I also have the issue detailed in this thread: NVIDIA Forums -> vista tv out

which although annoying you can get the Nvidia card to recognise the TV by rebooting the PC when the TV is on and set to correct source.

I've tried all possible forms of resolutions and Hertz rates from the nvidia control panel.

Reson for getting this card was because my Mobo can send digital sound through the HDMI connection on the 8400GS making things a whole lot easier to hook up to TV.

If any one has any ideas I'd be grateful as I've spent the last 2 days trying to figure it out. I personally think its Nvidia driver not coping, but it could be vista?

Thanks

John