Sites-enabled config and multisite

I have several servers and sites running multisite using easy engine. All but one works with the standard settings for domain mapping:

# Uncomment the following line for domain mapping listen 80 default_server; server_name_in_redirect off;

However, I keep getting errors when running nginx -t

nginx: [emerg] a duplicate default server for 0.0.0.0:80 in /etc/nginx/sites-enabled/

So I recommented those lines and was able to get my site running again, but of course, domain mapping is dead.

So I’m totally lost as to why I cant seem to uncomment those lines and get this particular server running, since my sites-enabled configurations are identical across all the servers I maintain and all the other ones work fine.

Bizarre. Did a whole migration from Xen to KVM which required having to reinstall NGINX. Then I was able to comment out those domain mapping lines and its all working again!