smtpout.us-phx.vox.secureserver.net has no MX records.
Question and response
Question
dig smtpout.us-phx.vox.secureserver.net. MX
Answer
The response has no answer records.
Authority
vox.secureserver.net. 3600 SOA ans01.domaincontrol.com. dns.jomax.net. 2026022701 300 600 1209600 3600
Additional
. 0 OPT ; payload 1280, xrcode 0, version 0, flags 0