No sound transferred from a notebook to TV with HDMI connection

My notebook is Acer TimelineX 4820TG, Windows 7 64 with Realtek audio hardwares. It has a HDMI port, and I use it to connect to my plasma TV. It does its job beautifully transferring both video and sound with only one cable connection. Recently, I found that many times the sound didn't come out from the TV speakers. The pictures from my notebook came out to TV ok but not for the sound. After spending hours of internet searching and trying, I finally managed to fix it. If you experience something like that, try this:

Go to Device Manager in Control Panel
Go to System Devices (not Sound, video and game controller branch as you might think) and look for High Definition Audio controller that marked with an arrow icon indicating this device is not working properly or is disable. Fix it there by updating the drivers or just enable it.


Now when you connect HDMI to TV, if it hasn't any sound on TV, go to a Sound setting in Control Panel (or you can go to a speaker icon on the tray, then right click it) and select Playback devices. Right there, you should see HDMI sound output. Select it and click Make Default.