Excuse me for being dumb here but surely the person using the same IP as I have given the empeg will have no idea that I have used or nor will the cable service provider as it does not connect to the internet?

The internet isn't the problem. The problem is the local-area-network, i.e., your neighborhood since you're on a cable modem. Someone in your neighborhood might want to use that IP address, and as long as the Empeg is answering pings on your neighborhood's network at that address, this other person will get an error message when Windows boots.

This is only a problem because you're plugging the Empeg directly into the network, without a NAT (network address translator) as a layer between your computers and the cable modem. Which brings me to...

I have also ordered a second ethernet card but this appears to be stuck in a postal strike at the moment. when this turns up I will plug the modem into one and the hub & empeg into another. This will then sort all of this out.

Exactly. This is essentially the same thing as the SOHO router I described in my last message, only you're using the computer and a piece of software to do the work. Into one card will be plugged the cable modem, which has your ISP's assigned address. Into the other card will be plugged the Empeg and any other computers in your house, and they will all share that single IP address through the NAT feature of the proxy software. Your computer will assign them all DHCP numbers such as 10.0.0.1, 10.0.0.2, 10.0.0.3, etc., and they will all communicate with the proxy server which will do the address translation for them. So it will solve the problem just fine for you.

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Tony Fabris