Apex domains cannot have CNAME records.
Question and response
Question
dig casscabletv.com. NS
Answer
casscabletv.com. 5 NS ns2.casscomm.com.
casscabletv.com. 5 NS web.casscabletv.com.
casscabletv.com. 5 NS ns.casscomm.com.
Authority
The response has no authority records.
Additional
web.casscabletv.com. 5 A 24.245.95.15
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0