Oddity - Two wireless signals available same MAC. Hacking?

Recently I noticed my Wireless connection is sometimes oddly slow, generally without any immediately noticeable interferance; ie by signal strength and enviormental observation.
As it happens today I updated my driver for my mini-PCI in my laptop, which also has a alternate wireless control app, other than the default XP version.
But now when I refresh the "visible sites" I get a 2nd visible network with the same MAC address as my access point. It tends to have a slight to very different signal stremgth, sometimes even more in terms of dBm. It should be noted that the 2nd available signal doesnt have my SSID (which is not broadcast BTW, WEP is on also, which I do know just keeps the normally honest person honest.)

So with the idea that it is a Netgear wg602 ver 3 G/B access point....
Am I getting hacked or is it more likely that is a function of the router listening for a B signal?

Thanks for reading all that and the input.

I feared it might be something like that. Is there software available that can determine where the spoofed AP is? I have two available laptops to do the work if needed. I am about to try the 'turn mine off and walk around the "yard" with my laptop...'

One almost certainty, if this is the case, is that its one of my near neighbors since it is fairly constant and not a horrble quality signal.

The problem I have is that my Tivo adaptor doesnt support WPA.

Thanks Blue!