Apex domains cannot have CNAME records.
Question and response
Question
dig vf.shawcable.net. NS
Answer
vf.shawcable.net. 5 NS a1-220.akam.net.
vf.shawcable.net. 5 NS pd1ns1.st.vc.shawcable.net.
vf.shawcable.net. 5 NS a6-65.akam.net.
vf.shawcable.net. 5 NS a9-67.akam.net.
vf.shawcable.net. 5 NS a8-66.akam.net.
vf.shawcable.net. 5 NS a3-64.akam.net.
vf.shawcable.net. 5 NS pd1ns2.cv.gv.shawcable.net.
Authority
The response has no authority records.
Additional
a9-67.akam.net. 1 A 184.85.248.67
a9-67.akam.net. 1 AAAA 2a02:26f0:117:0:0:0:0:43
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0