USB DAC How To

List DAC devices

$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: PCH [HDA Intel PCH], device 0: ALC269VC Analog [ALC269VC Analog]
Subdevices: 0/1
Subdevice #0: subdevice #0
card 0: PCH [HDA Intel PCH], device 3: HDMI 0 [HDMI 0]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: PCH [HDA Intel PCH], device 7: HDMI 1 [HDMI 1]
Subdevices: 1/1
Subdevice #0: subdevice #0
-->>card 1: DACHA200 [DAC-HA200], device 0: USB Audio [USB Audio]
Subdevices: 0/1
Subdevice #0: subdevice #0

Edit .asoundrc file with following

pcm.!default{
        type plug
        slave.pcm "usbdac_dmix"
}

pcm.usbdac {
           type hw # USB DAC device
           card 1     # check these value by "aplay -l" output!! something like "card 2: Device [USB PnP Sound Device], device 0"
           device 0  # check these value by "aplay -l" output!!
}
pcm.onboard {
            type hw
            card 0     # check these value by "aplay -l" output!! card 0: SB [HDA ATI SB], device 0: CONEXANT Analog [CONEXANT Analog]
            device 0  # check these value by "aplay -l" output!!
}
pcm.usbdac_dmix {
                type dmix
                ipc_key 1026 # must be unique!
                slave {
                        pcm "usbdac"  
 ## all following in this dmix section should be set according to your hardware. If you're not sure, don't try to add them!
                        period_time 0
                        period_size 1024
                        buffer_size 8192
                        rate 48000  # Fireye 2 support up to 48000Hz, please refer to your hardware spec.
                      }
}
pcm.onboard_dmix {
type dmix
ipc_key 1025 # must be unique!
slave {
        pcm "onboard"
 ## all following in this dmix section should be set according to your hardware. If you're not sure, don't try to add them!
        period_time 0
        period_size 1024
        buffer_size 8192
        rate 44100
      }
}

Enjoy The DAC Music!