Okay, this is going to be one of those times you need to understand when it comes to VGA port and Stereo Audio output this I what you need to do.
VGA to VGA on VGA port on the back of HDTV
Audio Stereo Headphone Jack 1/8 male adapter Y type audio L and audio R. This is one type of cable but if your HDTV only has 1/8 male lead to lead to inline cable for Stereo Audio you need to purchase that type over the 1/8 with Y adapter stereo audio cable.
On the PC, open the Control Panel
Type in Sound
Right click Manage audio devices
Click on Create Shortcut this will appear as speaker on your desktop
Double Click on Sound icon
Right click anywhere
Click on Show disable devices (check off)
Click on Show disconnected devices (check off)
Sound Playback
HDTV
Speakers
Headphones
Whatever you see listed above to match your connection make sure you set that to default.
Right click on the default
You have a menu of option features.
Configure Speakers
Test
Disable
Set as the default device
Set as the default communication device
Show disable devices
Show disconnected devices
Properties (additional settings)
Note: Once you have made the connection from the laptop to HDTV via 1/8 inline cable just run test to make sure you can hear the test code play on HDTV. If you do use 1/8 stereo Y cables instead with RCA Left/Right jack same method would apply to match those input connections on the back of your HDTV.
If you run into sound playback issues the laptop must not be using SPI instead it should be using 24-bit HD Sound it should be 16-bit Stereo sound you find those setting under Properties. The laptop should setup the correct settings. But if it doesn't you have to do it.
I have desktop and two laptops using HDMI to HDMI on HDTV. I had 1/8 incline stereo cable to HDTV via VGA to VGA. That works fine. But when you turn on the laptop and flip the panel up there will be no sound from the laptop speakers. To change those settings you would reverse the settings above to default stereo speakers on laptop. Can't have both on laptop speakers and HDTV Stereo speakers.