For the sake of discussion, let’s say my MIAB runs on a server called box.example.com. I have custom DNS records for this starting with
box.example.com A 123.456.789.100
I have a CNAME for the www subdomain pointing to a different domain
works fine and I can see the cname record with dig.
I’ve had this setup working before, and I can’t see the difference with what I’m doing now. I haven’t forgotten to end the names with dots. There’s only one record for each of the subdomains in question.