According to Midiman, you should use the "ASIOv1" Driver.This is considerd to be a Legacy Driver that will work with Digital Performer.Copy this driver into Digital Performers "ASIO Drivers" folder.Then launch DP, go to the basics Menu , then to the "Configure Audio System" menu, then choose "Configure Hardware driver". Here choose "ASIO" and then choose your Quattro ASIO driver.Now all of the I/O of the Quattro will appear in DP.