How to stream Amazon Prime Music

How have you configured the sound output for the PC?  In the settings area have you designated the DAC as where you want the sound to be directed, instead of the internal Computer Speakers?  Do you listen to other music from the computer via the usb connection?  If so then you may have to check the setting within Amazon.

I’m a bit confused, because your original post seems to imply that you have a DAC that connects to your PC by usb, but one of us seems to be missing something...Anyway, my setup is I have a Mac Air that is connected to the usb input of a Bryston DAC3.  I had to change the sound settings in the Mac to designate the Bryston as the desired output instead of the Computers internal speakers.  It’s been a while since I’ve used a Windows PC but they have something similar in their control panel, and as the last poster mentioned with some DACs Windows Computers need a special driver installed.
  I hope this helps