Win7 HDMI Audio Driver for IDT

Hi,
I have an Sony computer PCG 2D1M and I use the HDMI slot to connect with my Bose sound system.
Under Vista I had sound, after Upgrade Windows 7 Ultimate I have no sound, but all others works well.

My acutal driver is Sigma Tel High Definition Audio Codec, as producer is named IDT.
I tryied to get help form Sony support, but I got a not very helpful answer.

Can anyone help me?

Thanks JD

Hi jd40, and Welcome to the Seven Forums.

Tried to look up your Sony computer on the net and wasn't able to fine any specs. If you could put up a picture of the hooks on your computer it might help. Thanks Lee