Problem is you installed a Dell instead of a Mac.
Those SoundMax cards (actually just a few chips on the mobo) are crap; they have really screwy settings. If there's a "3D" sound setting(s) that you can find in the volume control panel you should set it to 0.
I know this only because I have the same card in my crap Dell that I use for Linux. Unfortunately ALSA under Linux provides greater flexibility than you may have under Winblows.
One more thing...there was a driver update for these things about 2 years ago. It resolved a "plays way too damn fast" problem, where everything coming out of the speakers sounded like the Chipmunks at 3/4 speed.