Relatek ALC889 and DTS Neo PC

Hi,

on a system with Realtek ALC889 (HD audio on Gigabyte motherboard GA-MA69VM-S3H), in the driver there is a feature called DST Neo PC. What I understand from this feature is that is supposed to output always 5.1 surround sound, from any audio source (MP3, movie...) even if the source is only stereo.

But, even if I know that this sound is a simulated 5.1, the driver introduces some artifact. The bass is smoothed and right after is amplified (ok the song for my test is Apologize from Justin, just because the trouble is easy to reproduce AND it's the only song I have at this moment... )

So my question is : is it just because the Realtek driver is really bad for doing the DTS Neo, or my version (1.67) had some trouble with this feature (I know there is a new version from the Realtek website but is not listed from the gigabyte website) ?

If the Realtek didn't do the job, does a discrete card will do the DTS Neo perfectly, without a glitch and when the source will switch to 5.1, handle it as is?

The speakers are Altec Lansing VS3251, Windows XP SP2, AMD 4200+ X2, 2GIG of RAM.

Thank you