pfSense Unbound "Phantom" Entry

Hi Folks - I just started playing with Home Assistant and IoT. The first thing that I did is create a new, separate interface for IoT ( - VLAN 101). I use pfSense’s Unbound for internal DNS services but IoT will be using a Pi-Hole instance on the IoT network (which resolves out to Quad4 - not my “internal” DNS).

The strangeness is that Unbound keeps adding pfSense’s IP address for IoT ( as an additional A record (and /etc/hosts) matching the hostname of pfSense. It does not show up in the lists of hosts in pfSense. I have shutdown Unbound and manually deleted the entries from /etc/hosts and /var/unbound/host_entries.conf and after a couple of minutes it shows up again.

Anyone have any ideas? This is more than annoying as 50% of the time it resolves to the correct (internal) IP of pfSense and the other 50% it is the IoT IP of pfSense.

*** Edit to add:
This only happens for the new IoT network. Other (internal) interfaces (VLANs/subnets) do not do this - for example the (VALN 25) does not add the additional entries.