awx_web won't start. Port Issue?

I just did a new install of awx using docker and when it starts the awx_web container stops immediately. When I look at the logs of the container I see this message:

Error: Another program is already listening on a port that one of our HTTP servers is configured to use. Shut this program down first before starting supervisord.
For help, use /usr/local/bin/supervisord -h

I cannot find another program anywhere that is using any of the ports listed in /.awx/awxcompose/docker-compose.yml. I have no other containers running. If I run sudo netstat -peanut I am not seeing any obvious conflicts.

What could possibly be the problem?