No audio through HDMI with HD 4400

Hi everybody. I have a sony vaio Pro 13 with Intel(R) HD Graphics 4400 and windows 8.1. When connecting the laptop via HDMI to the TV i can see the video but not sounds. In the Audio settings i can clearly see an HDMI device but it's always NOT PLUGGED IN.

Anyone can help me?

I can all the driver audio and video update, and the only issue that i can notice is that is impossible for me to install the HD graphics 4400 driver version 15.x because my computer is "not suitable" . I have the version 10.18.10.3304