List of playback audio
aplay
**** List of PLAYBACK Hardware Devices ****
card 0: sndrpihifiberry [snd_rpi_hifiberry_dacplus], device 0: HiFiBerry DAC+ Pro HiFi pcm512x-hifi-0 [HiFiBerry DAC+ Pro HiFi pcm512x-hifi-0]
Subdevices: 1/1
Subdevice #0: subdevice #0
Speaker test
speaker-test -c2 -t sine -f 880
USB microphone test
arecord -D plughw:1,0 -d 5 -f out.wav && aplay -D plughw:0,0 out.wav