Once you own your modem no matter what happens YOUR MODEM will be at fault.
I could call my cable company (starts with a "C"
)and say my service is out and I can see the cable running to my house is laying in the street. Their response would be "I am sorry sir we have no other reports of service outages or downed wires in your area. According to our records you are using a personally owned modem. So you will need to contact your modem manufacturer for support."