I have a Benchmark DAC1 USB that I have been using for a couple of years.  I recently tried to connect it to a Dell Inspiron 6400 laptop and the DAC1 is not recognized.  The laptop detects a device but does not recognize what it is and cannot find a driver.  I am running Windows XP SP3 with all the latest patches.  My laptop recognizes a home made generic dac based on the PCM2702 DAC chip as USB Speakers without a problem.

Thanks for any help.