HDMI to HDMI, no sound, tried all usual

Hi all, unsure if correct forum as reading other replies on same issue sometimes it's been called a video card or sound card issue and others settings so here goes.

I have a direct HDMI to HDMI from laptop (Sony Vaio AR21S) to tv (Toshiba 37XV555DB). I have picture but no sound.

I have definitely had sound using HDMI from this laptop before but it was returned from repair (motherboard problem), seems to be working fine otherwise. It's a different tv from before (was previous a Sony Bravia) so don't know if tv problem.

Rang Toshiba, they checked I had it set to receive sound via HDMI, said I had and that problem was with computer.

Have checked all the setting and looked at other posts on this issue. Some of the settings I don't have.

Example when I right click on the speak I don't get "Playback Devices" I get open volume or adjust audio properties. If I select audio properties I get windows box with Volume, Sounds, Audio, Voice, Hardware tabs and nothing in any of them related to HDMI or anything like my TV device. The audio device is "Sigma Tel Audio" unless I plug in my Creative Soundblaster X-Fi Go and that comes up.

In control panel I have this "Sound Reality Audio" panel. It has settings for enabling HDMI output which is selected. I've checked all settings with this website http://www.sony.ca/view/333.htm, it still doesn't work but the site does confirm that the AR-Series definitely supports video and audio through HDMI.

I'ved tried running several things with noise, IntervideoWinDVD with DVD's inserted, Windows Media player for mp3 tunes and movies (in avi format with codecs installed) and movies and music through media player classic (in avi format with codecs installed).

Nothing gives me sound through the TV :-(

Plus! I tried using an standard audio jack from the headphone socket to the RCA connections on the TV, nothing, not a peep!

Frankly I'm at a loss as to what to do. Sony are useless, they're so busy trying to assert that there's nothing wrong with their technology that they can't give you any practical ideas.

Toshiba are adamant the tv is fine which I tend to agree, using same cable in same HDMI socket I get audio and sound.

Can someone please help?

P.S. Don't know if it's needed by it's an NVidia Geforce Go 7600 graphics card in laptop and it has media centre edition 2005, blu-ray disc drive.

I'm having the exactly same issue. If you got the solution please let me know. I'll really appreciate your response.

What solution you have tried yet just let me know which is better for me to provide you the solution regarding same. Did you checked the HDMI cable which might be faulty and that is why not performing well with the system of yours. Also it is advisable to update the driver of your system which will resolve the issue related to same.