_spf.mediatemple.net has no CNAME records.
Question and response
Question
dig _spf.mediatemple.net. NS
Answer
The response has no answer records.
Authority
mediatemple.net. 900 SOA a1-245.akam.net. dnsadmin.mediatemple.net. 2021120754 10800 3600 1209600 10800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0