HDMI no sound

So I configured I just got a m17x with crossfire 5870 and thought it would be fun to plug into my current home theater.

But the laptops doesn't switch to HDMI sound and my reciver reports no speakers signal from the laptop. The laptop keeps using the interal or analog out speaker jacks while hooked up via hdmi.

Am I doning something wrong?

Also on a side note when I put the picture on my 720p LCD as exteneded it looks like a 2:44 movie instead of 16:9.

 

You need to go to playback devices and manually set it to use the hdmi.

 

All the seemingly useful opitions are greyed out.

 

Yes you need to manually set it, and if that doest work restart your system while connectd

 

For your video, when you set your screen to an external device, you'll have to manually set the resolution on the laptop, so when you press the button to switch screen displays, it will automatically display the right amount of pixels putting video on your tv into the correct resolution .

 

Only way I got it to work was to install ati hdmi driver from realtek.
Go here and download it. After you run the installation reboot and hdmi sound should work.

 

Thanks for the suggestions guys. I did a reboot first before trying new drivers and that worked. Kinda miffed that I want to plug my laptop in I have to reboot.

I also ended up to uncheck "Hide modes this monitor can not display" and tell it go 1080p for my tv to fill its picture.

 

On your tv now, if the native resolution is 1080p, an option should come up saying 1:1 or dot per dot, something to that effect, and thats pretty much stating that what your tv is displaying also isnt being distorted. TVs come with settings that will take small resolutions and bloat them to fill the screen, stretching a regular 480p to a screen thats native res is 1080p. So check the tv too to make sure the proper size and pixels are being displayed without a post tv setting.