I'm just posting this here for people who are googling and can't find what they are looking for.
I am running a HP DV6 Laptop with windows 7.
The blue volume bar that appeared on the screen when using the touch controls stopped appearing. I could still adjust volume however it would not show the bar.
To fix this. (Basic instructions)
- Find the volume Icon in the bottom right hand corner.
- Right-Click on it and select Volume control options
- Find option that is similar to ATI HDMI output.
- Make sure this is checked and click ok.
Test it. It should now appear on screen again.