installed pulse audio (no errors seen)

sudo systemctl enable pulseaudio
returns
Failed to enable unit: File pulseaudio.service: No such file or directory

Just for grins I ran

./piardopc -c GPIO=12 8515 plughw:CARD=udrc,DEV=0 plughw:CARD=udrc,DEV=0
Below are the results. Note the second line. Same results with GPIO=23

------------------------------------------------------------------------------

ARDOPC Version 1.0.4.1i-BPQ
 GPIO=12 could not be opened
ARDOPC listening on port 8515
Capture Devices

Card 0, ID `ALSA', name `bcm2835 ALSA'

Card 1, ID `udrc', name `udrc'
  Device hw:1,0 ID `Universal Digital Radio Controller tlv320aic32x4-hifi-0', name `', 1 subdevices (1 available)
    2 channels,  sampling rate 8000..96000 Hz

Playback Devices

Card 0, ID `ALSA', name `bcm2835 ALSA'
  Device hw:0,0 ID `bcm2835 ALSA', name `bcm2835 ALSA', 7 subdevices (7 available)
    1..2 channels, sampling rate 8000..48000 Hz
  Device hw:0,1 ID `bcm2835 ALSA', name `bcm2835 IEC958/HDMI', 1 subdevices (1 available)
    2 channels,  sampling rate 44100..48000 Hz

Card 1, ID `udrc', name `udrc'
  Device hw:1,0 ID `Universal Digital Radio Controller tlv320aic32x4-hifi-0', name `', 1 subdevices (1 available)
    2 channels,  sampling rate 8000..96000 Hz

Opening Playback Device plughw:CARD=udrc,DEV=0 Rate 12000
Opening Capture Device plughw:CARD=udrc,DEV=0 Rate 12000
ARDOPC listening on port 8515
Input peaks = -856, 793
terminating on SIGINT