I do not hear anything when I click on a soundbite to audition
Auditioning in Digital Performer 4 & later (and AudioDesk 2 & later) will output out of your first output bundle.
Go to the Studio > Audio Bundles menu and set the first output bundle to be the outputs you wish to monitor from. In Digital Performer 3, go to Windows > Audio Bundles.
For AudioDesk 1, auditioning for the PCI-324 and PCI-424 system will output out of the monitor output selected in the MOTU PCI Audio Console. For the 896HD & 828mkII, it will output out of the first output stream: Phones 1-2.