The driver IDs as "AM2/AICASoundDrv990421/Ver1.60" and "Sequencer 1.27 99/03/16 Y.Takeda" (ETA: which is basically the same driver as VF3TB). From a quick glance it looks like it's something of a midway point between the Saturn driver and Manatee, but that could be wrong. There are several blocks throughout RAM with the signature "DTPK" but none of the normal SMSB/SMPB manatee stuff.
Soul Reaver famously used interactive music, and thus I would presume it's going to be painful to rip (early attempts at various developed-by-Rare N64 games with interactive music usually resulted in all the possible tracks playing at once, which was not real listenable ;-)
