Funny thing, that ... I had better results with PowerDVD (when it was installed) than with Intervideo WinDVD.
My lappy's sound system is Realtek AC97. I installed
AC3 Filter with which you can adjust the master volume before it becomes controlled by the soundcard's volume control, so in effect you have 2 volume controls working in series, which is handy for faint tracks.
An interesting extra is the ability to control the volume of the voice channel independently of background music, plus other things if you have surround sound.
AA