Ensoniq AudioPCI ES137x is the chipset used on the Soundblaster PCI 128-card.

When you add the module for ES137x (1370 or 1371) to the kernel, recompile and restart your system with the new compiled kernel, your soundcard should work.

At least, this works fine on my system. I have the same soundcard and I used the ES1371-module when recompiling the kernel.

I hope this was helpfull.