the only time I ever got dns problems was when I was using ICS and my firewall wasn't properly configured
Have you tried the pc mac address in the xbox and a direct connection to the modem using a straight netwrok cable (if you were using ICS before it would have been a crossover hence the no ip address)
With NTL and a standalone modem (is it standalone) you shouldn't even have to clone the pc's mac address for it to work (with a set top box you do though)
I only clone my mac address so i don't have to reboot the modem before i switch on the xbox
Have you tried the pc mac address in the xbox and a direct connection to the modem using a straight netwrok cable (if you were using ICS before it would have been a crossover hence the no ip address)
With NTL and a standalone modem (is it standalone) you shouldn't even have to clone the pc's mac address for it to work (with a set top box you do though)
I only clone my mac address so i don't have to reboot the modem before i switch on the xbox

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