I need some help getting the right driver loaded and enabled for sound on an HDMI display. Long story, but I had problems extending the display from an HP EliteBook 8440P using the integrated VGA port in both the laptop and the HP USB 2.0 dock. Video would run for a while, then blink out and default back to no second display selected. No great explanation for this other than I suspect problems I can't fix in the driver and or graphics. No driver choice for this, that I tried, improved the result. Also tried the options from the HP support site, including the drivers for the USB dock that included DisplayPort video. The display I'm extending to also has HDMI. The HP USB2.0 dock has DisplayPort, so I did a passive cable conversion to the display HDMI port and find the video to work as expected. The audio, however, does not. In the image of W7 Pro-64 on the laptop, I have no HD Audio device listed in Control Panel/Sound, or Device Manager/Sound, video and game controllers. I did a clean W7 Pro-64 install on an identical laptop and find a sound device in Control Panel called Digital Audio (HDMI) using a Microsoft High Definition Audio Device, version 6.1.7601.17514 signed by Microsoft. So far, no combination that I have tried of Windows Update, scan for changes or show disabled or disconnected sound devices on the original laptop gets me any closer. Web searches related to downloading that driver haven't got me there either. I don't know how to copy a driver from one laptop to another. Ideas?