Monitor Speakers not working when connected via HDMI to laptop

Hi,

I've recently purchased a Samsung T23A750 monitor and to my disappointment when I try to watch a movie the built in speakers are not functioning. I have a Sony Vaio Z216GX connected via HDMI to the monitor (HDMI-DVI) port. I can definitely see the video, but no audio is playing from the speakers. The built in speakers are not at fault- I did a self-diagnosis of the monitor and the speakers seem to work fine. I also set the monitor as the default for the audio and even when Win 7 says its functioning properly, the speakers still don't work. Conversely, setting the default to my PC speakers work fine. I'm sure its not the HDMI cable- I used the same one to hook my pc to my tv with everything working fine. Any ideas??

make sure you have the latest drivers for the hdmi can check by going to the windows start bar and right clicking on computer and choosing manage then click device manger and open the tab were it says sound,video and game controllers if you see somthing related to hdmi and has a yellow triangle then right click on it and update software if no yellow triangle is there try it anyways if that doesn't help then post here again, hopefully someone who knows more about hdmi can help also because i never had hdmi but ive had audio problems with my speakers before and this is how ive fixed it before

Hey!

Thanks for the reply. Unfortunately, i dont see anything related to HDMI when i open the sound, video, game controllers tab. However, I did update for whatever was there - Intel (R) Display Audio and Realtek High Def Audio. I'll attach what my playback devices look like and Device Manager. It's interesting because it seems like my PC is giving out an audio signal, which is why I'm assuming when looking at the playback device the audio (in green bars) is shifting up and down for the monitor. I can't seem to have the monitor speakers recognize and play the audio! I was even with sony support for an hour to no avail.