root@odroidc2:~# ps aux | grep networkaudiod
root 937 5.6 0.4 18360 7100 ? S<Lsl 16:23 23:43 /usr/sbin/networkaudiod
root 4828 0.0 0.0 4280 904 pts/0 S+ 23:20 0:00 grep --color=auto networkaudiod
I am running it as root on vanilla Armbian 64 (Ubuntu Xenial):
Linux odroidc2 3.14.79-odroidc2 #20 SMP PREEMPT Fri Dec 30 18:46:17 CET 2016 aarch64 aarch64 aarch64 GNU/Linux
I suspect the default configuration during install has set the nice-ness to -10:
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
937 root 10 -10 17976 6736 1696 S 17.0 0.4 24:27.54 networkaudiod
Finally, the dirty secret is that I used the stretch deb packages from your repo - there are no Ubuntu packages for ARM Xenial in your repo.
I hope that helps.