This information is provided for experimenters. No support will be provided by NW Digital Radio. Some underlying software is not well tested and may break in unexpected ways. Not all applications will have access to the virtual sound cards created.
Use at your own risk, backup prior configurations and be prepared to delete any modifications and to restore prior configurations.
Modify Your Configuration
Edit /boot/config.txt and include the line
Save and reboot
Create or Edit /etc/asound.conf
Obtain the file from github
curl -L -s https://raw.githubusercontent.com/nwdigitalradio/udrc-tools/master/udrc-setup/asound.conf > asound.conf
You can put it in ~/.asoundrc for a single user
mv asound.conf .asoundrc
Or make it apply for the whole system by editing /etc/asound.conf or replacing /etc/asound.conf
sudo cp asound.conf /etc/asound.conf
Verify The New Devices
This should return the following information
Discard all samples (playback) or generate zero samples (capture)
Default Audio Device
Direct sample mixing device
Direct sample snooping device
Direct hardware device without any conversions
Hardware device with all software conversions
Use in direwolf.conf
For example in direwolf.conf, use logical sound card din6...
PTT GPIO 23