6935G 5.1 problems

I've just done a clean install of Windows 7 64bit and installed the latest Realtek HD driver (2.42) from their site, selected 5.1 in the sound properties through Windows and Audio Manager but when I playback media the sound is still tinny and only 2.0.
I haven't installed anything else and let Windows find the other drivers for my 9600M GS etc

This is the second time I've installed the OS as facing the same problem before and thought it might have been a corrupt installation or something.

Anybody able to help me?

 

I've sort of fixed the issue temporarily by installing the audio drivers for the 6530G (version 6.0.1.5888). 5.1 seems to work but after playing the media for a while the speakers will start to buzz as though the bass is failing. If I stop it (close media player) and start it again then the audio will be fine for a bit again.

Has anyone installed HD audo drivers for this model successfully on Windows 7 64bit?

 

Now have 2.32 installed and works better than anything previously, although now the sound sometimes echoes. Seems fine using VLC and temperamental with flash videos online, but watching a trailer with quicktime is very 'echoey'!

If there is anyone who can provide assistance, please reply - starting to regret getting the laptop now!