Gremlins Emerge with Switch to Windows 7

I have had generally good PC audio experiences using Windows XP.

In fact, I have viewed with skepticism a lot of the PC optimization threads as I found with USB into external DACs it was pretty straightforward to get pretty darn good sound.

So I am dismayed tonight to have finally purchased a new, and much faster laptop which operates with Windows 7.

In an A/B comparison with my old laptop, using the same USB cable into my desktop system, the new laptop sounds HORRIBLE.

Can anyone please offer a simple, lean and mean configuration in Windows 7 for exporting audio via USB?

Thank you,