They are probably allowing the usb ports to only supply the minimum amount of current.
If the dac has an external power supply or integrated battery you aren't using, that may do the trick too.
Other usb devices may also be drawing current and preventing the DAC from working.
If the dac has an external power supply or integrated battery you aren't using, that may do the trick too.
Other usb devices may also be drawing current and preventing the DAC from working.








