If the card volume is low or non existant, standard trick is to check your x:\mmos2\mmpm2.ini file and in any line under the "mixer sections", what the
"PARMSTRING=BALANCE=50,VOL=80,INPUT=LINE,GAIN=70,OUTPUT=SPEAKER" line values for GAIN and VOL are.
Not all mixers can change, or change the correct VOL and GAIN parameters and I've had no problems with the mixers for SBAWE32 and 64 when I used them. If you do need to manually change these parameters, boot to maintence mode or boot from a CD/DVD otherwise your edits will be lost. You can sometimes change the values and simply hit the reset button as long as nothing else is running but it is not the recommended way of doing it, you could end up with a corrupt mmpm2.ini file.
As already pointed out, check the cards irq and ports are not conflicting with something else as the AWE drivers are not high IRQ aware, they can only use the old base interrupts. If you can check under a different operating system where the AWE card works to double check the card's settings and adjust those on the drivers line in your config.sys file. I now remember when I let the AWE32/64 driver figure it out automatically that it did not work. driver switches should be in one of the packages.