Z Class Output Digital Audio signal from Displayport to HDMI

Z Class Output Digital Audio signal from Displayport to HDMI

Hello,

I have a z90dw model, I flash it with the last WES2009 image available for this model.
I bought a Displayport + audio to hdmi adapter to be able to have the video and audio on a LCD TV.
The model z90dw has a T56N APU , this APU include have a Radeon HD6320 embedded.
AMD documentation tell that this graphic card support displayport audio, and it tell also that passive displayport to hdmi adapter can be used to output the audio throw hdmi.

When WES2009 boot only the video is available on my HDMI LCD TV.

Do I need to change any settings to have the audio output throw displayport.
I have test by booting usb stick with linux distribution (debian/opensuse) but it doesn't work.

Could you help me ?

Is there any specific requirement on the hdmi version supported by the LCD TV ?
Do I need to install a specific driver ?
How could I identify if the issue coming from displayport configuration or from the adapter ?

Thanks for your help.

Ackwel.