Only 1 output not 2

Hi, I'm new to this forum and search some help for preview.
I have a macbook air and a usb sound card,in addition to the built in.
Cross DJ (free version) do not give me possibility to preview track on usb with headphone and to listen on ACTON speaker (USB or Bluetooth plugged)
If i take a look in audio setting i see only one output , even if create aggregate or multiple output in MIDI setting. May be i do something wrong.
I have a macbook air and a usb sound card,in addition to the built in.
Cross DJ (free version) do not give me possibility to preview track on usb with headphone and to listen on ACTON speaker (USB or Bluetooth plugged)
If i take a look in audio setting i see only one output , even if create aggregate or multiple output in MIDI setting. May be i do something wrong.