What're you using for soundcard?
You could parse the output of aplay and arecord with grep and awk at runtime to then edit the direwolf conf file with those values with sed
In my case this is what I see
? ?~ arecord -l
**** List of CAPTURE Hardware Devices ****
card 2: Device [USB Audio Device], device 0: USB Audio [USB Audio]
? Subdevices: 1/1
? Subdevice #0: subdevice #0
so if I want my usb device, I'm going to run something like
? ?~ echo "plughw:$(aplay -l | grep USB | awk -F '[ :]' '{print $2}'),$(aplay -l | grep USB | awk -F '[ :]' ?'{print $9}')"
plughw:2,0
then use sed to replace the active field
Brad