Currently your domain is pointing at the IP address 184.108.40.206 - which is not that of Voice, which is why it isn't working.
If you try again, setting it to point to 220.127.116.11 then it should work fine.
There's usually a delay after changing it before anything happens, but once set, be patient, and all will be well.
Once you've set it, you are welcome to send an email to email@example.com for me to check that the settings seem to be correct. (if you email rather than posting on the forums it'll save so many email notifications going out to our users!)
Joe - Voice Admin