Hi Ramiro, this is on a rpi4, isn't it? I'm curious, don't you have
problems (system freezes) using usb audio with xhci (when audio is
used for a while, not instantly)?
By the way, there is a pretty active ham radio community on sdf.org.
I recommend you to ask for an account there (if you are not already
a member) and post your experience with netbsd on the bboard's
HAMRADIO list.
I'm not a ham myself, but I've good memories at a friend's house
before the internet took over, and I check often that list to see
what gizmos they use now.
Regards.
adr