No sound in Gnome under Mandrake 8.2

I have Mandrake 8.2 setup on a system that includes a Soundblaster PCI card.
Sound works fine in KDE, but I cannot get it to work in Gnome.  The first
time I tried to enable sounds in Gnome it seemed to work, but the next time
I started Gnome my desktop changed from blue to black and sound is disabled.
I can restore the initial conditions by deleting my .gnome file as suggested
on www.gnome.org, but the same desktop color change and loss of sound occurs
after I again enable sound.

It has been suggested that the problem is that my video card and sound card
are sharing an interrupt, which may be correct. But this same hardware works
in KDE, so why should it be a problem in Gnome?

Vic Roberts