No Audio via HDMI to TV

Hello all,

Okay, so I have seen this thread posted a few times but after trying out all of the methods posted with no luck I thought it was time for me to ask for some help.

The problem:

Sound is working fine through my laptop speakers but when I connect it to the TV via HDMI cable the sound still comes through the laptop.

I was previously running Windows Vista Home Premium and it worked absolutely fine. As in, the sound came out of the television speakers when I connected the notebook to the TV. I recently upgraded to Windows 7 Home Premium and since then it does not work. I would appreciate if anyone could help me.

Right now the default sound output device is: Speakers/Headphones - SigmaTel High Definition Audio CODEC. The other two listed are Realtek Digital Output (Optical) - Realtek High Definition Audio and Digital Output Device (HDMI) - SigmaTel High Definition Audio CODEC.

When I try either of the other two sound does not work at all. With the Realtek one it seems to recognize the sound but I don't hear it anywhere and with the HDMI one, it doesn't work at all i.e. Fails to play test tone. I have installed all the latest drivers according to manufacturers.

Thanks in advance,

Imran

A more comprehensive computer spec:

Sony Vaio VGN-AR71M

• Platform Technology Intel Centrino
• System Type Notebook
• Built-in Devices Stereo speakers, wireless LAN aerial
• Width 41.6 cm
• Depth 30 cm
• Height 3.5 cm
• Weight 3.8 kg
• Processor Intel Core 2 Duo T8100 / 2.1 GHz
• Multi-Core Technology Dual-Core
• 64-bit Computing Yes
• Data Bus Speed 800 MHz
• Features Enhanced SpeedStep technology
• Chipset Type Mobile Intel PM965 Express
• Cache Memory
• Type L2 Cache
• Installed Size 3 MB
• RAM
• Installed Size 4 GB / 4 GB (max)
• Technology DDR2 SDRAM - 667 MHz
• Configuration Features 2 x 2 GB
• Storage Controller
• Type Serial ATA
• Serial ATA Interface Serial ATA-150
• Storage
• Hard Drive 300 GB - Serial ATA-150 - 4200 rpm
• Optical Storage
• Type DVD±RW (±R DL) / DVD-RAM / BD-ROM - integrated
• Read Speed 24x (CD) / 8x (DVD) / 2x (BD)
• Write Speed 8x (CD) / 8x (DVD±R) / 2x (DVD-R DL) / 4x (DVD+R DL)
• CD / DVD Rewrite Speed 8x (CD) / 4x (DVD±RW) / 5x (DVD-RAM)
• Card Reader
• Type Card reader
• Supported Flash Memory Cards SD Memory Card, Memory Stick, Memory Stick PRO, Memory Stick Duo, Memory Stick PRO Duo
• Display
• Display Type 17" TFT
• Max Resolution 1440 x 900 ( WXGA+ )
• Widescreen Display Yes
• Features X-black
• Video
• Graphics Processor / Vendor NVIDIA GeForce 8400M GT
• Video Memory 256 MB
• Audio
• Audio Output Sound card
• Compliant Standards Microsoft WSS 1.0/2.0, High Definition Audio
• Features Sound Reality technology
• Audio Input Microphone
• Notebook Camera
• Camera Type Integrated
• Sensor Resolution 1.3 Megapixel
• Capture Resolutions 1280 x 1024
• Input Device(s)
• Type Keyboard, touchpad
• Telecom
• Modem Fax / modem
• Max Transfer Rate 56 Kbps
• Protocols & Specifications ITU V.90, k56Flex, ITU V.92
• Networking
• Networking Network adapter
• Wireless LAN Supported Yes
• Data Link Protocol Ethernet, Fast Ethernet, Gigabit Ethernet, IEEE 802.11b, IEEE 802.11a, IEEE 802.11g, IEEE 802.11n (draft)
• Compliant Standards IEEE 802.11b, IEEE 802.11a, IEEE 802.11g, IEEE 802.11n (draft)
• Expansion / Connectivity
• Expansion Slots Total (Free) 2 ( 0 ) x memory ¦ 1 ( 1 ) x CardBus - type I/II ¦ 1 ( 1 ) x ExpressCard/54
• Interfaces 1 x IEEE 1394 (FireWire) - 4 PIN FireWire ¦ 3 x Hi-Speed USB - 4 PIN USB Type A ¦ 1 x headphones - output - mini-phone stereo 3.5 mm ¦ 1 x microphone - input - mini-phone 3.5mm ¦ 1 x audio - SPDIF output ¦ 1 x audio / video - HDMI - 19 pin HDMI Type A ¦ 1 x display / video - S-video output ¦ 1 x display / video - VGA - 15 pin HD D-Sub (HD-15) ¦ 1 x network - Ethernet 10Base-T/100Base-TX/1000Base-T - RJ-45 ¦ 1 x modem - phone line - RJ-11
• Miscellaneous
• Features Security lock slot (cable lock sold separately)
• Power
• Power Device External
• Battery
• Technology Lithium Ion
• Installed Qty 1
• Run Time (Up To) 1.5 hour(s)
• Operating System / Software
• OS Windows 7 Home Premium
• Major Software Microsoft Office 2007 Ultimate, Adobe CS4 Master Collection, Command & Conquer Red Alert 3, The Sims 3, Zoom Player and iTunes.