Issues starting unbound on boot

[Markus Wipp]

Hi all, 

I currently face an issue, where I don’t know further on why this happens and what I could do about it.
I hope that this is the correct list to ask my question. If not please let me know where else I might try my luck.
I installed unbound from ports, configured it and can start / stop it from command line with service unbound start without any problems.
But whenever I reboot the machine it just doesn’t get started. The only information I was able to find out so far can be found in /var/log/messages:
root: /etc/rc: WARNING: failed to start unbound

I tried to run with rc_debug=“YES” and got the following:
root: /etc/rc: DEBUG: checkyesno: unbound_enable is set to YES.
root: /etc/rc: DEBUG: run_rc_command: start_precmd: start_precmd
root: /etc/rc: DEBUG: checkyesno: rc_startmsgs is set to YES.
root: /etc/rc: DEBUG: run_rc_command: doit:  limits -C daemon /usr/local/sbin/unbound  -c /usr/local/etc/unbound/unbound.conf 
root: /etc/rc: WARNING: failed to start unbound

uname -a:
FreeBSD h01dc01 11.2-RELEASE-p9 FreeBSD 11.2-RELEASE-p9 #0: Tue Feb  5 15:30:36 UTC 2019     root at amd64-builder.daemonology.net:/usr/obj/usr/src/sys/GENERIC  amd64

Thanks for any useful hints in advance
Markus