Darla cards Rev 1 have audio problems. The way to tell if thecard is Rev 1 is to carefully remove the Darla sticker from the chip on the board. Underneath, you will find a set of 3 serial numbers. The middle number designates Rev. If that serial number starts with a number 1, the card is Rev 1. The card should be returned to the manufacturer for exchange. Please make sure the customer returns the card complete with driver disc