Hmmm..."aplay -l" gives me something promising:
```
**** List of PLAYBACK Hardware Devices ****
card 0: J314 [MacBook Pro J314], device 0: Primary (*) []
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: J314 [MacBook Pro J314], device 1: Secondary (*) []
  Subdevices: 1/1
  Subdevice #0: subdevice #0
```