pi-hole on 14.04 server

I am trying to setup a pi-hole server on a ubuntu 14.04 server. Pi-hole is a dns server that blocks ads on webpage and on youtube. From what I know, it works great on a raspberry pi but I don't have one but I have an old pc running ubuntu 14.04 that I hope can do the job.

I followed the instructions given on this page: Guide: Installing PiHole on an Ubuntu Server to Block Ads on your Network but I encounter problems with dnsmasq

If everything goes according to the instructions given in the link, dnsmasq should be listening to the ip adress of the server. But in my case, the dnsmasq service listens to 0.0.0.0:53.

I edited dnsmasq.conf and changed the line

listen-adress=192.168.1.133,127.0.0.1

but when I stop/start dnsmasq I get the error message

* Starting DNS forwarder and DHCP server dnsmasq 
dnsmasq: failed to create listening socket for port 53: Address already in use
                                                                     [fail]

Even when dnsmasq is stopped,

netstat -anlp | grep -w LISTEN

gives the following:

tcp        0      0 0.0.0.0:53              0.0.0.0:*               LISTEN      4557/dnsmasq

So my question is:

how to force dnsmasq to listen to the proper ip adress?

Regards