Jim GM4DHJ ... brought next idea :
Keep getting calls from a paki or indian call centre from a george smith or
james patterson etc regarding my "BT internet being in big trouble".......I
tell them to feck off as I am with Virgin....does anybody know what the scam
is?......

They will likely offer to get you to install something so they can take
control of your system and keylog, to steal all your banking passwords.

Feck Off is the correct way to deal with them..