mid.dyn.suddenlink.net has no MX records.
Question and response
Question
dig mid.dyn.suddenlink.net. MX
Answer
The response has no answer records.
Authority
mid.dyn.suddenlink.net. 7200 SOA authns1.alticeusa.net. abuse.alticeusa.com.mid.dyn.suddenlink.net. 2014012302 7200 1800 1209600 7200
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0